Which Stablecoins Move the Market? An Analysis of Volume Spillovers

This report analyzes cross-stablecoin trading-volume spillovers across eight USD stablecoins - USDT, USDC, DAI, TUSD, GUSD, FRAX, USDD, and USDJ - covering January 2023 to December 2024. We aggregate daily CEX and DEX volumes, transform them as first differences of log(1+V), and run lagged OLS regressions (up to 3-day lags, p<0.05) to build a system-wide spillover network that quantifies how past volume in one stablecoin predicts volume changes in others. The results show a concentrated core: USDC is the leading transmitter of trading activity (32.4% of total spillovers), followed by USDT (19.7%). A mid-tier - GUSD (12.1%), USDJ (11.3%), and DAI (11.1%) - exerts moderate influence, while FRAX (6.7%), USDD (5.3%), and TUSD (1.4%) sit at the periphery. Taken together, USDC and USDT account for ~52% of all measured spillovers, indicating that monitoring their volume pulses is most informative for system-wide liquidity shifts.