Approach

1. At first found contracts of bridges that they bridge tokens between Ethereum chain and Optimism chain which are as follows:
   • 0x10e6593cdda8c58a1d0f14c5164b376352a55f2f
   • 0x99c9fc46f92e8a1c0dec1b1747d010903e884be1
   • 0xaba2c5f108f7e820c049d5af70b16ac266c8f128
   • 0xf20c38fcddf0c790319fd7431d17ea0c2bc9959c
2. Then by using ethereum.core.ez_eth_transfers table I extracted data which includes volume of token bridges between Ethereum chain and Optimism chain.
3. Then I calculated daily and monthly bridges between two chains for ETH / USDT / USDC / DAI

Two bar charts below shows how has volume of $ETH bridges performed on daily and monthly time frames since April 2021

Even though both has increasing trend but as we can see volume of $ETH bridges to Optimism has been dominant and this is visible on daily and monthly charts.

On daily charts we see that volume of $ETH bridges into Optimism goes up to 65K $ETH on Aug 4, 2022 and on the other hand it goes only up to 3.4K on Jun 8, 2022 from Optimism to Ethereum.

On monthly charts constantly increasing trend is visible for both charts and as we see volume of $ETH bridges to Optimism maxed on August with 121K $ETH and on the other hand it maxed on June with only 13K $ETH.

Even though both has increasing trend but as we can see volume of $USDT bridges to Optimism has been dominant and this is visible on daily and monthly charts.

On daily charts we see that volume of $USDT bridges into Optimism goes up to 16M $USDT on Aug 5, 2022 and on the other hand it goes only up to 10M $USDT on Oct 3, 2022 from Optimism to Ethereum.

On monthly charts constantly increasing trend is visible for both charts and as we see volume of $USDT bridges to Optimism maxed on August with 63M $USDT and on the other hand it maxed on October with only 11M $USDT .

Two bar charts below shows how has volume of $USDT bridges performed on daily and monthly time frames since July 2021

Two bar charts below shows how has volume of $USDC bridges performed on daily and monthly time frames since August 2021

Even though both has increasing trend but as we can see volume of $USDC bridges to Optimism has been dominant and this is visible on daily and monthly charts.

On daily charts we see that volume of $USDC bridges into Optimism goes up to 81M $USDC on Aug 5, 2022 and on the other hand it goes only up to 48M $USDC on Aug 30, 2022 from Optimism to Ethereum.

On monthly charts constantly increasing trend is visible for both charts and as we see volume of $USDC bridges to Optimism maxed on August with 277M $USDC and on the other hand it maxed on October with 141M $USDC .

Two bar charts below shows how has volume of $DAI bridges performed on daily and monthly time frames since August 2021

Conclusions

As we saw in this dashboard volume of all bridges such as volume of ETH, USDT, DAI or USDC bridges has been increasing throughout their time frame and there was huge increase in volume of ETH, USDT, DAI and USDC bridges from Ethereum to Optimism in early days of August specially August 4th and 5th and also as we saw on monthly charts on August the most bridges of all tokens from Ethereum into Optimism happened.

And we see that September 5th was a day that two out of 4 observed tokens maxed out which are DAI and USDT.

Even though both has increasing trend but as we can see volume of $DAI bridges to Optimism has been dominant and this is visible on daily and monthly charts.

On daily charts we see that volume of $USDC bridges into Optimism goes up to 35M $DAI on Aug 4, 2022 and on the other hand it goes up to 45M $DAI on Sep 5, 2022 from Optimism to Ethereum.

On monthly charts constantly increasing trend is visible for both charts and as we see volume of $DAI bridges to Optimism maxed on August with 137M $DAI and on the other hand it maxed on September with 50M $DAI .