Formula to count a column if it is completed each day.

I have a spreadsheet that I need to complete an addition of all of the fields that were completed on that day. For example, I have a starting total of $4,000 which was derived from 30 cells in a column, in which only 10 cells make up the total. I need to show that if I complete 5 more cells today, what is the total of the cells I completed today.

Is there anything in a particular column that indicates when the totals were entered ? Like a date ?