What did the volume look like in decentralized exchanges on Ethereum during that period?

As can be seen in the charts above, at the beginning of the second week of May, the volume of swaps(in USD) on DEX has started to increase and this increase has continued until the weekends and has decreased sharply in the last one or two days of the week. This pattern is almost the same for all DEXs. The largest increase in swap volume in one day is related to the uniswap-v2 DEX, which has increased 13 times on May 13 compared to the previous day, and also the largest decrease in swap volume related to this exchange, which occurred on May 14, and the swap volume is 32 times less than the previous day! The highest volume of swaps in the second week of May is related to uniswap-v2 DEX with the amount of 3.919 billion dollars. the second and third ranks are related to Curve, which has a trading volume of 2.56 and 1.78 billion dollars, respectively.

What assets were being sold/bought most?