The min/max block will continouosly monitor another block (or expression) and report on its current minimum/maximum value since the simulation started, or, as we saw in the last experiment, until it is reset. The result is a plot like this:
However, if we want to use this value for a subsequent calculation, we are often not interested in the current minimum or maximum. We want the maximum from when the block reset last time.
In the example above, one could imagine a conservative calculation which uses the maximum value from the previous month to calculate the dose of a person exposed by the poisoned soil.
The trick is to use another block, the snapshot, in order to capture the maximum value each time a month begins.
You can download the solution here