Why do we have "Global Load Caching Mode" in occupancy calculator?


When I am using occupancy calculator excel sheet that is released by nVidia, I enter the compute capability, total shared memory, and whether the L1 cache is enabled or not (option 1c “Select Global Load Caching Mode”).
I am wondering, why L1 cache may change the occupancy calculator?
Could someone clarify how L1 cache enabled/disabled option may affect the occupancy with an example?