How to sum under conditions?

[Corner]

Hello there, I’m trying to do a sum of money amounts, based on their year.
Could you help me to write the formula ? I would like the output sum to be the sum of every rows when the row’s year equals the data item year :

Thanks in advance !

[Corner]

For those who wonder, here is the solution :

I love Weweb but there is a true issue with the modal display when setting up formulas (not enough room for all elements!)

[Joyce]

Nicely done @Corner And thanks for taking the time to share the solution you found with the rest of the community here, really appreciate it!