Found 2 биржи where Usual USD is traded for USDT. According to the data on 25 December the most optimal price to exchange USD0 for USDT is ₮1 for 1 Usual USD. This rate is fixed at Uniswap (v3) at the maximum trading volume of the pair USD0/USDT - 402.3 ths. USDT.
The maximum daily trading volume is observed in the USD0/USDC trading pair at Curve (Ethereum) and reaches ₮ 55,062,168.72 (17.27% of the exchange's total trading volumes) at the price ₮ 1 per 1 USD0.