To hold the divisions you create in the chart, Go to your data tab and select the resync properties. On the last page you want to select the “Do not create” and “Apply active markers after synchronization”
The “Do not create” will hold your formatting as well as the divisions. The “Apply active markers” will distribute any color codes you have created to the new incoming boxes into the software. After you have selected those you can then select the resync data and it will hold your formatting and divisions.