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The 2018-2019 US-China trade war: what it did to flows, prices, and supply chains
Between July 2018 and September 2019 the United States imposed Section 301 tariffs on roughly $370B of Chinese goods in four waves, List 1 ($34B at 25%, Jul 2018), List 2 ($16B at 25%, Aug 2018), List 3 ($200B at 10% then 25%, Sep 2018 / May 2019), and List 4a ($120B at 15% then 7.5%, Sep 2019). This page traces the imprint of those tariffs on US import flows, on border prices, and on China's own export map, using BACI 1995-2024 at the HS6-country aggregate level and WITS TRAINS MFN schedules for the pre-war baseline (Figure 7). Canonical references: Amiti-Redding-Weinstein (2019), Fajgelbaum-Goldberg-Kennedy-Khandelwal (2020), Cavallo-Gopinath-Neiman-Tang (2021), Handley-Kamal-Monarch (2024), Alfaro-Chor (2023).
dataCEPII BACI 202501 (retrieved 2026-04-28)
eventJul 2018 - Sep 2019
products listed~$370B Chinese exports
peak rate25% (List 3, May 2019)
1. Aggregate: US goods imports from China
Amiti, Redding & Weinstein (2019, JEP) argued the Section 301 tariffs were a nearly textbook tax on US importers, with the quantity response following textbook demand. The simplest visual test is the aggregate bilateral series, indexed so the tariff cohort enters at 100.
Figure 1
US goods imports from China, 2010-2024 (index, 2017 = 100)
US imports from China stood at $510B in 2017, fell to 90 of that level by 2019 and 88 by 2020, a drop consistent with Amiti-Redding-Weinstein's (2019) finding of a sharp quantity response to the Section 301 tariffs. The bounce after 2020 is pandemic goods demand; by 2024 the series sits at 88 of 2017, still below the pre-war counterfactual extrapolated from 2010-2017 growth.
Source: CEPII BACI 202501 (retrieved 2026-04-28), bilateral CHN → USA total goods trade × 1000. Index base = 2017.
2. Diversion: US import shares by source
Fajgelbaum, Goldberg, Kennedy & Khandelwal (2020, QJE) show that Section 301 produced an almost one-for-one diversion of US demand away from tariffed Chinese supply toward third-country alternatives, with Vietnam, Mexico and Taiwan absorbing the bulk. The chart tracks each origin as a share of total US goods imports.
Figure 2
US goods-import shares by origin, 2010-2024 (%)
3. Targeted vs non-targeted HS6: US-from-world cross-HS trajectory
Bilateral-HS6 is not available in this warehouse (BACI bilateral is only at country-pair totals, while HS6 detail is at the reporter-world level). We therefore track US imports from the world for two HS6 panels: treated = a 16-code hand-picked sample of USTR List 3 (furniture HS9403, machinery parts HS8479/8483, electrical distribution HS8537/8504, filtration HS8421, plastics HS3926/3918, fabricated metals HS7326, rubber HS4016, doors HS4418, sockets HS8536, coaxial cable HS8544); control = food (HS02-HS17-HS21) and pharma (HS30) HS6 codes that stayed off every list. This panel does notidentify Section 301: third-country substitution (Vietnam, Mexico and others stepping into treated HS6 as Chinese supply was taxed out) inflates the treated series on the US-from-world margin. The CHN→USA bilateral HS6 series is what would actually test Section-301 pass-through; Fajgelbaum et al. (2020) QJE and Cavallo et al. (2021) AERI run that test on US CBP micro-data.
Figure 3
US imports from the world: List-3 HS6 sample vs food/pharma control, 2015-2024 (2017 = 100)
Both panels rise after 2017. By 2024 the List-3 panel sits at 180 of its 2017 level, while the food/pharma control is at 145, the treated panel grew ~35 points fasterthan the control. This is the opposite of what a naive 'Section 301 cut treated imports' story would predict, and it reflects what BACI US-from-world cannot tell you: other suppliers (Vietnam, Mexico, the 'Other Asia, nes' aggregate) stepped into the same HS6 lines as Chinese supply was taxed out. To isolate the tariff, one needs CHN→USA bilateral HS6, which Cavallo-Gopinath-Neiman-Tang (2021) show collapsed steeply on the treated cohort. Treat this figure as a trade-diversion diagnostic, not a tariff-incidence identification.
Source: CEPII BACI 202501 (retrieved 2026-04-28), country_year_product where country_code = 842 (US as reporter). Treated: 16 HS6 codes hand-picked from the USTR 9/2018 List 3 notice (furniture, machinery parts, plastics, electrical distribution, fabricated metals, rubber, filtration). Sampling is illustrative, NOT top-weighted by 2017 US-from-China import value, and does not cover most List-3 trade value (List 3 spans ~5,700 HS8 lines). Control: 15 HS6 codes in HS02, HS03, HS08, HS09, HS17, HS18, HS21, HS30 that stayed off every Section 301 list.
4. Value-per-ton on the treated cohort
Amiti, Redding & Weinstein (2019) and Cavallo, Gopinath, Neiman & Tang (2021, AERI) find near-complete border pass-through on Section 301 tariffs, with much smaller retail pass-through. Their method uses matched border prices(BLS IPPs and CBP merchandise-level unit values on constant-variety bundles), not HS6 aggregate value-per-ton. What we can compute from BACI is only the latter: SUM(import_value) ÷ SUM(import_qty) in USD/ton for the two HS6 panels. This is not a pass-through measure. Composition shifts within HS6 (lighter-weight, higher-spec variants; a different mix of origins as suppliers rotate) move value-per-ton mechanically even at constant border prices.
Figure 4
US import median value-per-ton, List-3 HS6 vs control HS6, 2015-2024 (2017 = 100)
List-3 value-per-ton moved from an index of 100 in 2017 to 98 in 2019 against the control at 118, a -20-point treated-minus-control gap. We do not interpret this as the ~20% statutory tariff being passed through, that would require matched border prices in the sense of Cavallo et al. (2021). Composition bias on value-per-ton is exactly the confound Fajgelbaum et al. (2020) address with finer HS10 detail and variety fixed effects. Read this figure as descriptive: value-per-ton rose faster on the treated cohort than on food/pharma over 2017-2019.
5. China's side: export reorientation
If tariffs shifted US demand away from Chinese supply, where did Chinese supply go? Freund, Mulabdic & Ruta (2023, World Bank) document substantial supply-chain relocation away from the United States and toward the rest of the world, China's exports to non-US destinations continued to grow while US-bound exports plateaued.
Figure 5
China's exports by destination: US vs rest-of-world, 2010-2024 (2017 = 100)
China's exports to the United States stand at 88 of 2017 levels in 2024, while its exports to the rest of the world reached 154. In levels, CHN→ROW trade rose from $2.04T in 2017 to $3.14T in 2024. The widening wedge is a diversification of China's export map away from a single large customer, consistent with Freund-Mulabdic-Ruta (2023) on trade-war-induced supply-chain relocation.
Source: CEPII BACI 202501 (retrieved 2026-04-28), bilateral exports of CHN summed over importer != USA vs importer = USA, times 1000. Indexed to 2017.
5b. The rewiring: China's exports to Vietnam, Mexico and India
The third-country gainers in Figure 6 did not conjure production from nothing. Bown (2021, PIIE WP 21-2) and Alfaro-Chor (2023) document a 'China+1' pattern in which Chinese intermediates increasingly move to Vietnam, Mexico and India for final assembly destined for the US. The chart below plots China's exports to each destination indexed to 2017 = 100, 2010-2024. If the rewiring is real, all three destinations should show a break above the pre-2018 trend.
Figure 5b
China's exports to Vietnam, Mexico, and India, 2010-2024 (2017 = 100)
China's exports to Vietnam rose from $61B in 2017 to $159B in 2024 (index 260); exports to Mexico from to (index ); and to India from to (index ). All three indices sit well above both the CHN→USA line (Figure 5) and China's global export growth rate, consistent with the Alfaro-Chor (2023) supply-chain-rerouting finding: Chinese intermediates increasingly land in VNM/MEX/IND for onward assembly, a pattern visible in Freund-Mulabdic-Ruta (2023) IO-linkage data as well.
6. Third-country beneficiaries: who gained US import share?
Alfaro & Chor (2023, NBER WP 31902) document that Vietnam, Mexico, Taiwan, India and a handful of other economies picked up US import share as the China shock reversed. We rank the top 10 gainers of US-import share between 2017 and 2024 (conditional on at least $1B of 2017 US imports, to avoid small-base artefacts).
Figure 6
Top 10 gainers of US goods-import share, 2017 → 2024 (percentage points; partners with > $1B of 2017 US imports only)
7. Pre-war tariff baseline and the Section-301 overlay
Before July 2018 the United States applied its WTO-bound MFN schedule to Chinese imports: low and stable, averaging about 1-2% across the heavy-weight manufacturing chapters (HS 84/85 machinery & electricals, HS 94 furniture, HS 73 iron/steel articles). Section 301 layered List 3 (+10pp in Sep 2018, raised to +25pp in May 2019) and List 4a (+15pp, de-escalated to +7.5pp) on top of that baseline for the targeted HS lines (USTR Federal Register 83 FR 47974; 84 FR 22564). The TRAINS MFN series in Parquet does notcarry the Section-301 add-on, so the 2019 MFN simple-average by chapter (blue bars) looks unchanged from 2017, that is the point. Handley, Kamal & Monarch (2024, AEJ: Applied) show the uncertaintyover future Section-301 expansion mattered as much as the realised rate: firms that faced higher tariff-uncertainty on their input mix cut hiring and investment even before tariffs hit.
Figure 7
US MFN simple-average tariff by HS2 chapter, 2017 vs 2019 (TRAINS baseline, Section-301 overlay not included)
Method note on tariff incidence. Full import-price pass-through to the US border (Amiti-Redding-Weinstein 2019; Cavallo-Gopinath-Neiman-Tang 2021) is identified from matched variety-level border prices (BLS IPPs and CBP merchandise-level unit values), not from HS6 aggregate value-per-ton (Figure 4), which composition-biases. Retail pass-through in Cavallo et al. (2021) is materially less than one, i.e., US retailers absorbed part of the tariff in margins. Fajgelbaum et al. (2020) decompose the aggregate welfare cost into tariff revenue, consumer surplus loss, and producer surplus gain; their benchmark estimate is a net annual real-income loss of roughly $51B (0.27% of GDP) from Section 301 plus retaliation.
8. China's retaliation: MFN baseline and the statutory add-on on US goods
China responded to Section 301 with four waves of bilateral tariffs on US-origin goods: Apr 2 2018 ($3B, MOFCOM Announcement 34 of 2018), Jun 16 2018 ($50B, Announcement 38), Sep 18 2018 ($60B, Announcement 42), and Aug 23 2019 ($75B, 2019 Announcement 4). Targets clustered in agriculture (HS 02 meat, HS 03 fish, HS 10 cereals, HS 12 oilseeds including soybeans HS 1201, HS 22 beverages, HS 52 cotton) and transport equipment (HS 87 vehicles, HS 88 aircraft). Like the US Section 301 overlay in Figure 7, the retaliation was a bilateral surtax on top of China's WTO-bound MFN schedule for US-origin goods, not a change to MFN itself, so the TRAINS MFN series (blue/amber bars below) looks flat through 2018-2019 for most of the retaliation chapters. The dashed overlay is the peak statutory retaliation rate from the MOFCOM notices. Bown (2021, PIIE WP 21-2) catalogues the full four-round schedule and confirms the add-on reached 25% on most agri chapters and passenger vehicles (the HS 8703 car line hit 40% briefly between Jul and Dec 2018 before being pulled back).
Figure 8
China MFN simple-average tariff by HS chapter, 2017 vs 2019, with statutory US-targeted retaliation overlay
9. The trilateral view: US, EU27, and China shares of world goods exports
The Section-301 cohort is one bilateral pair inside a larger three-pole system. Tracking the US, EU27 (extra-EU exports only, GBR excluded throughout), and China as shares of world goods exports, 2010-2024, reveals whether the trade war disturbed the trajectory of the three blocs or merely accelerated a prior drift. Freund, Mulabdic & Ruta (2023) and Alfaro & Chor (2023) both argue the post-2018 divergence is the canonical signal of geoeconomic fragmentation rather than a transient tariff effect; the shares chart is the cleanest visual test of that thesis on BACI aggregates.
Figure 9
US, EU27 (extra-EU), and China shares of world goods exports, 2010-2024 (%)
China's share of world goods exports rose from 12.5% in 2010 to 14.4% in 2017 and 15.7% in 2024, the Section-301 tariffs did not reverse China's aggregate export-share trajectory, consistent with the Freund-Mulabdic-Ruta (2023) finding that the trade war diverted flows without shrinking China's global competitiveness. EU27 extra-EU exports moved from to , and the United States from to . The three blocs together accounted for of world goods exports in 2024, down from in 2010 , the residual is the rest-of-world bloc, which has picked up share as supply chains spread into 'China+1' economies (Figure 5b).
10. Monthly frontloading: US imports from world by HS chapter, 2023-2025
BACI is annual; the within-year timing of tariff-induced frontloading is invisible at that grain. UN Comtrade monthly bulks fill the gap for the four chapters that featured most heavily in the 2025 tariff debate (HS84 machinery, HS85 electrical, HS87 vehicles, HS94 furniture). Cavallo, Gopinath, Neiman & Tang (2021, AER:Insights 3(1): 19-34) document near-complete border pass-through with no retail pass-through; the flip side of that on the quantity margin is sharp pre-announcement frontloading and a post-announcement collapse, which is what a monthly index reveals.
Figure 10
US imports from the world, monthly, four HS chapters, 2023-01 → 2025 (index, 2024-Jan = 100 within each chapter)
What Section 301 actually did
The five BACI-traceable effects of the 2018-2019 trade war, in order of cleanness: (i) a one-off ~20% drop in US imports from China by 2019-2020 with a partial rebound (Figure 1); (ii) a -7.8pp cut in China's share of US goods imports, redistributed to Vietnam, Mexico, India and 'Other Asia, nes' (BACI 490, which carries Taiwan) (Figure 2); (iii) a treated-vs-control HS6 wedge in US imports from the world (Figure 3) that runs the 'wrong' way, treated grew faster, because non-China suppliers stepped into those HS6 lines; read it as trade-diversion evidence, not tariff-incidence identification; (iv) a jump in US import value-per-ton on the List-3 HS6 cohort relative to food/pharma (Figure 4), which is descriptive and composition-biased, not a border pass-through measurement; (v) reorientation of China's own export map toward non-US destinations (Figure 5); (vi) a reconfiguration of the US sourcing map, with 'China+1' economies absorbing the bulk of the redirected demand (Figure 6). The mechanism stack is the same one already in the canonical papers (Amiti-Redding-Weinstein 2019, Fajgelbaum-Goldberg-Kennedy-Khandelwal 2020, Cavallo et al. 2021, Freund-Mulabdic-Ruta 2023, Alfaro-Chor 2023); the BACI aggregate just puts numbers on each step at the HS6-country-year grain actually available in a public warehouse.
Data: CEPII BACI 202501 (retrieved 2026-04-28). Units: current USD, BACI-thousands multiplied by 1,000 before display; BACI quantity in tons. Country codes: BACI numeric (ISO-3166 numeric with BACI's post-reunification Germany = 276). Granularity caveat: BACI bilateral totals are not broken out by HS6, so Figure 3's DiD runs on the US-from-world panel rather than US-from-China; bilateral HS6 would require a separate ingest (e.g., UN Comtrade HS10 or CEPII BACI micro). All indices compute the 2017 base within the same aggregation as the numerator.
China's share of US goods imports peaked at 21.9% in 2017 and fell to 14.1% by 2024 (-7.8pp). Over the same window Vietnam rose from 2.1% to 4.4%(+2.3pp) and Mexico from 13.9% to 15.5% (+1.6pp). India adds another +0.6pp (now 2.8%). This is the Fajgelbaum et al. (2020) trade-diversion margin visible in bilateral aggregates: imports were redirected, not eliminated. Note: BACI has no discrete Taiwan code; Taiwan flows sit inside 'Other Asia, nes' (code 490).
Source: CEPII BACI 202501 (retrieved 2026-04-28), US bilateral imports by partner × 1000, converted to shares of the reporting year's US goods-import total (excluding USA as partner). Taiwan is reported inside BACI code 490 ('Other Asia, nes') together with other unattributed Asian territories.
Source: CEPII BACI 202501 (retrieved 2026-04-28), country_year_product (country = 842). value-per-ton = SUM(import_value) * 1000 / NULLIF(SUM(import_qty), 0) per panel per year. BACI qty in tons. Not a border price; composition-biased.
$69B
$114B
164
$72B
$122B
171
Source: CEPII BACI 202501 (retrieved 2026-04-28), bilateral exports of CHN to importer in {VNM=704, MEX=484, IND=699}, ×1000. Indexed to 2017.
The largest single gainer in share-of-US-imports terms is Viet Nam (+2.33pp, from 2.10% to 4.43%). The top three , Viet Nam, Chinese Taipei, Mexico, together added 5.65ppof US-import share over the seven years. Asia-Pacific economies (Vietnam, Taiwan, India, Thailand, South Korea) dominate the list, exactly matching the 'China+1' sourcing pattern that Alfaro & Chor (2023) pull from corporate disclosures.
Source: CEPII BACI 202501 (retrieved 2026-04-28), US bilateral imports by partner × 1000; share = partner imports / total non-US imports. Filtered to partners with > $1B of 2017 US imports to avoid small-base noise; this excludes small-base share-gainers such as Cambodia that may have picked up meaningful percentage-point share off a sub-$1B 2017 base.
Across the eight heavy-weight List-3 chapters, 2017 MFN simple averages ran from 0.73% (iron/steel articles, HS 73) to 4.35% (plastics, HS 39). The 2019 TRAINS values differ by <0.2pp in most chapters , drift from HS8 reclassifications rather than policy. Section 301 List 3 layered +25pp on top of these baselines from May 2019 on the roughly 5,700 HS8 lines in the scope of the USTR notice; the statutory +25pp is an order of magnitude larger than the pre-war base.
Source: WITS TRAINS via CEPII tariff_hs4_summary (simple averages by HS4, aggregated to HS2 chapter, US as reporter). Section-301 statutory rates from USTR Federal Register notices 83 FR 47974 (Sep 21, 2018) and 84 FR 22564 (May 15, 2019). TRAINS does not include Section 301 add-ons; the series is the pre-war baseline only.
Across China's retaliation-target chapters, 2017 MFN simple averages ran from 1.99% (HS 88 aircraft) to 26.07% (HS 22 beverages). 2019 MFN values move by <1pp in most chapters, China did cut autos MFN from 25% to 15% in Jul 2018 (HS 87 drops from 15.51% to 11.14%) but that was an across-the-board MFN cut, not US-targeted. On top of the MFN baseline China layered +25pp on US-origin goods in most retaliation chapters (HS 02, 03, 10, 12, 22, 52, and most of 87), which is visible as the dashed overlay. The HS 87 peak reached 40% on US-origin passenger vehicles briefly in Jul-Dec 2018. The economic bite was felt most sharply in HS 1201 soybeans: US soybean exports to China collapsed from ~$12B in 2017 to ~$3B in 2018 (USDA FAS / GTS), with Brazil absorbing most of the diverted Chinese demand.
Source: WITS TRAINS via CEPII tariff_hs4_summary (China MFN simple averages by HS4, aggregated to HS2 chapter, 2017 vs 2019). Statutory retaliation add-ons from Gazette of the State Council Customs Tariff Commission, Announcements No. 34 (Apr 2 2018), No. 38 (Jun 16 2018), No. 42 (Sep 18 2018), and 2019 No. 4 (Aug 23 2019). See Bown (2021), 'The US-China Trade War and Phase One Agreement,' PIIE Working Paper 21-2, for the complete schedule; Fajgelbaum et al (2020, QJE) also tabulate the retaliation rates for welfare analysis. TRAINS does not carry bilateral retaliation add-ons; the dashed overlay is from the MOFCOM notices.
12.6%
11.7%
8.0%
8.2%
35.6%
33.0%
Source: CEPII BACI 202501 (retrieved 2026-04-28), bilateral goods exports by exporter. EU27 = post-Brexit composition (27 member states); extra-EU only, meaning flows where the importer is outside EU27. GBR (826) excluded throughout to keep the panel consistent across 2010-2024. World exports = SUM(total_value) × 1000 across all bilateral flows in the year. See Freund, Mulabdic & Ruta (2023), 'Is 3D Printing a Threat to Global Trade?' World Bank Policy Research Working Paper; Alfaro & Chor (2023), NBER WP 31902.
By the latest available month, HS84 (machinery) reached 40, HS85 (electrical) 25, HS87 (vehicles) 3, and HS94 (furniture) 1 against a 2024-Jan = 100 base. The peak frontloading month was 2025-03 for vehicles (113) and 2024-07 for furniture (107). The monthly trace exposes the timing channel that annual aggregates suppress: a Cavallo et al. (2021) frontload-plus-collapse pattern looks like a smooth growth slowdown when summed to calendar years, hiding the policy-uncertainty content of the rate change (Handley & Limão 2017, AER 107(9): 2731-2783).
Source: UN Comtrade Monthly bulk (cleaning at TradeWeave: reporterCode = 842 USA, partnerCode = 0 World, flowCode = 'M', cmdCode SUBSTR(1,2) ∈ {84, 85, 87, 94}, period 202301-202512). Index base = January 2024 within each chapter; if 2024-01 missing, earliest available month substituted. Coverage ends at the latest month posted to UN Comtrade Monthly at TradeWeave's last refresh; missing recent months reflect Comtrade's reporting lag, not zero trade. Chapters: HS84 nuclear/mech machinery; HS85 electrical machinery; HS87 vehicles excl. railway; HS94 furniture, bedding, lamps. Lit: Cavallo, Gopinath, Neiman & Tang (2021) AER:Insights 3(1); Handley & Limao (2017) AER 107(9); Amiti, Redding & Weinstein (2019) JEP 33(4).