The previous cache has been refactored to stop it from growing indefinitely. As discussed in Browser-Side Cache
The cache is backed by a map (associative array) from "figures" to "sum". There is also a queue of these "figures" keys, so that least recently used figures are removed from the map (as well as the queue) when the capacity is full.
Fill in as many fields as you like, then "Add" to add them up.