Tables: How do I copy and paste a formatted table and retain row height?

I've created a table of 3 rows, all formatted with different heights. I wish to extend the table with an identical 3 rows underneath (identical to the previous 3 formatted rows in terms of style and row height). Whenever I add 3 extra rows to the existing three, they all result in a default row height size. I select the first 3 formatted rows and copy, paste into the new 3 below, but when I do, the rows remain their default height. How do I copy, paste and retain the formatted sizes from the original rows?