Can I change panel width in a dashboard using Simple XML?

**I have 3 single panels and a table on a row in a dashboard** *...* *...* *...*table $TheGood$table $TheBad$table $TheUgly$table This, That, and More; **However, I would like to have each single only take up 15% of the row, and the remaining 55% taken up by the table. Currently, the row gives each panel 25% space for its content (4 panels split 4-ways gives 25% for each panel). Is there any way to override the defaults using simple xml?**