Two-way fixed effects DiD comparing Truist to four control institutions after the February 2019 BB&T/SunTrust merger announcement. 677,037 matched complaints.
0.111
DiD estimate (δ̂)
+11.8%
Implied increase
0.014
p-value (HC3)
[0.022, 0.201]
95% CI
Pre-Period Quarterly Growth RatesParallel trends support
Pre-period growth rates broadly comparable across institutions — no outlier pattern before the merger.
+0.98%
Truist
+0.42%
JPMorgan
+1.96%
Citibank
-0.64%
Wells Fargo
-2.14%
Bank of America
Post-Merger Complaint Change by Product
Checking/Savings
+8,556
Credit Reporting
+4,712
Vehicle Loan
+1,380
Debt Collection
+973
Credit Card
+970
Mortgage
-1,442
Checking/savings accounts account for 73.1% of total incremental positive volume post-merger.
Two-way fixed effects: institution (αᵢ) + quarter (λₜ). Standard errors: HC3-robust. Control group: Bank of America, Wells Fargo, JPMorgan Chase, Citibank.
DiD estimates are directionally informative. Control institutions are substantially larger than Truist; log transformation and institution FEs partially address size differences. Maximum observed z-score: 1.50 (no anomalous spikes at z > 2.0).