Adding times in a list box

[daved2424]

I currently have a list box which displays the length of an item. I.e.
2.23
8.12
2.05
6.14
3.11

In a second list box next to it I want to display the start time of each item if they were to be run sequentially. I.e.
2.23 0.00
8.12 2.23
2.05 10.35
6.14 16.49
3.11 20.00

The start time needs to be recaculated everytime a command is fired on the form so it is updated everytime an item is added or deleted from the list box. How would I achieve this?

[sw_is_great]

what is the connection between the first list box and the commands u run. do u mean that the listbox1 contains the commands ?????