add rows dynamically to the existing excel with Jxl

The existing functionality has an excel sheet, in code a copy of it is made and calculations are done based on the values from DB. It also has templates of charts

Now i need to insert dynamic rows in between the existing rows and chart. These rows should be from a particular row say 32. When i try to insert, it is inserting as the first row. Is there any way for dynamically generating the rows without changing the existing one and adding in between. The no. of new rows depend on the input. I am using Jxl.