Sum inside dataview and print the result

I want to print all the reading time I have spent on a book

Every time I read I write down a short summary and put with data view the time I’ve been reading.

When I make a query with dataview, it gives me my summaries and the reading time that, by pieces, I have invested.

How can I print the sum of those times?

What I’m trying to do

It occurred to me that using the table plugin with excel formulas I can do sums and other operations, but my idea is to do it with dataview, to make a query according to the book I read. With tables the process would be very static.

Thanks in advance