Checked Running Total of asp.net Gridview without Loop

Question

Hi,

 

I am using an asp.net gridview. the first column in the gridview is checkbox and the second column is amount. 

Assuming the gridview has 5000 rows, when the user checks the checkbox , i want to calculate the checked amount and display it in some label.  similiarly when the user uncheck , it should be recalculated.

how can i acheive this without using loops to avoid performance issues?