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Price Per Share and ATI Submission

5. Calculate the price per share​

Input the price per share of the contract. This informs how much the position is worth in terms of the underlying token(s).

1-for-1 redemption price​

If the position is redeemable 1-for-1 for its underlying token, you can input the number 1, and you're done!

Math formulas​

If the contract requires a calculation and values from methods called on a contract, you should build that calculation in the input field.

  • For example, the price-per-share of Compound's cUSDC token is calculated by calling the exchangeRateStored method on the cUSDC contract, which returns the price per share in terms of the underlying token (USDC).
  • You then need to adjust this value to be in terms of the underlying token's decimals, which is 6 for USDC, and you add 10 to the decimal.

The calculation would look like this:

@exchangeRateStored(CErc20) / 10 ^ (@decimals(FiatTokenV2_2) + 10)

Note that the CErc20 and FiatTokenV2_2 are the contract names of the cUSDC and USDC tokens, respectively, as we needed to get the decimals of the underlying token to adjust the price per share.

tip

If you are unsure of the method to call on the contract to get the price per share, you can refer to the contract owner's app documentation site, as they will often explain how to calculate the value of their positions. If you are still unsure, you can ask in the Zapper Discord for help and we can help you figure it out.

5.1 Calculating price per share for multiple underlying tokens​

If the App Token has multiple underlying tokens, you can calculate the price per share for each underlying token and sum them together.

Each underlying token will have its own price per share calculation. Input the calcuation for the price-per-share of that token in the box.

For example, on a Uniswap V2 pool token contract, you would calculate the price per share of each underlying token and sum them together. The calculation would look like this:

For token0:

(@_reserve0(UniswapV2PoolContract) / 10 ^ @decimals(token0Contract)) / 
    (@totalSupply(UniswapV2PoolContract) / @decimals(UniswapV2PoolContract))

For token1:

(@_reserve1(UniswapV2PoolContract) / 10 ^ @decimals(token1Contract)) / 
    (@totalSupply(UniswapV2PoolContract) / @decimals(UniswapV2PoolContract))

Where UniswapV2PoolContract is the contract name of the Uniswap V2 pool token, token0Contract and token1Contract are the contracts of the underlying tokens.

The interpreter will then sum these together to get the total price per share of the pool token.

6. Check the previewed value of the position​

After inputting the contract address, underlying token address, and price per share, you can check the previewed value of the position on the right hand side panel. This will show you the value of the position in fiat, such as USD, as well as the value of the underlying token(s) in fiat. This will help you confirm that the osition interpreter is working as expected.

  • If you're unsure if you got the postion's pricing right, consider checking the token owner's app site, as they will often list the values of their positions.
  • Additionally, if the token trades on a DEX, you can check the price of the token on DEXScreener or something similar.

7. Associate the position interpreter with an app (optional)​

Once your interpreter is working as expected, you can optionally associate the position interpreter with an app. You should select the app that owns the contract and deployed it onchain. This will allow Zapper to show the position's balance to users in our UI as being associated with the selected app, along with any other positions the user has on that app.

  • To see the list of apps available to associate the interpreter with, start typing in the "Select App" input box to search Zapper's database for the relevant app.
  • If you cannot find the right app to associate the interpreter with, you can type in that app's name and we will add it to our database and associate this interpreter with the app.

8. Submit the position interpreter​

Once you've inputted all of the above, go ahead and submit the interpreter. This will place the interpreter into a Pending state in your My Submissions page.

After submission, Zapper Admins will review the interpreter to ensure it is working as expected.

  • If the interpreter is good to go, it will be approved by the Zapper team, and you will receive a notification in your notification tray (in the top right of the page).
  • If there are any issues, Zapper will reject your interpreter and provide commentary on what the issue was. You can then make the necessary changes and resubmit the interpreter for review again.
  • Once your interpreter is approved, you will see it reflected on the Leaderboard, and users will be able to see their balance of the positions in the Zapper UI. Additionally, you'll be able to see the number of users who have the position in their wallet in your My Submissions page, so you can see the impact you have across all Zapper users!