Hi Alexis,

Are the summary and this expression in the group footer?
It’s possible to do with JavaScript. I’ll add an example tomorrow.

no
is on page body

Isn't the summary2 is a summary control? Summary control can be in the Page Footer, not a Page Body.

sorry
is on Column Footer

And there will be only one column on the page, right?

yes

Here's an example.

The value of the tax will be printed using the pPageTax internal parameter.
We can't use the value of summary directly so it is necessary to calculate it in the script, the SUM for one page will be stored in the report.page_sum property.

1. Add the following expression in the summary:
$P(pPageTax)

2. Reset the sum in the report pre_add_page script:
report.page_sum = 0;

3. Calculate SUM in the post_place script of the Page Body (reportbody1 object)
report.page_sum += report.cursor.columnValue( 'amount' );

4. Calculate the pPageTax value in the pre_place script of the Column Footer:
report.setParameterValue( 'pPageTax', 0.105 * report.page_sum );

If you don't need to print the tax depending on the statetax field value, you can use the print_if property of the expression

Here's an example.

The value of the tax will be printed using the pPageTax internal parameter.
We can't use the value of summary directly so it is necessary to calculate it in the script, the SUM for one page will be stored in the report.page_sum property.

Why can't we use the value of a summary expression? It's listed as a property (roducts:vstudio:help:report_editorroperties_inspector:summary_field" target="_blank" rel="nofollow">http://valentina-db.com/docs/dokuwiki/v9/doku.php?id=valentinaroducts:vstudio:help:report_editorroperties_inspector:summary_field).

It seems silly to have a summary expression on a report, then have to replicate the summary function in the script just so we can use the result elsewhere.