The 3rd pane from the right in the Status Bar shows the size in LADDER WORDS (not rungs) and the max size supported in the PLC. It looks like 00023/07680 (e.g. 23 words out of 7680).
To determine the number of rungs, you can display the rung numbers on your ladder view (versus rung addresses). Right click on the ladder view and choose Options... The under the Number Rungs group, click the radio button BY RUNG (versus BY ADDRESS). If you want ALL NEW VIEWS to display the rung number versus the address, click the Apply options to NEW VIEWS (in addition to CURRENT VIEW that should already be checked).
fyi, if you have DS100, the limit is 100 WORDS not 100 RUNGS, so you should only care about instruction addresses (not number of rungs).