Displaying TimeSpan as largest interval (with units)
The numbers 22.0, 50.0, 40.0, and 500.0 are "magic numbers" (non-obvious hard-coded numbers with no given meaning).

Since they're not commonly used with time, thus are not obvious, you should make the reader aware of their meaning.  This will also improve readability.

Two options for doing this include:


making them into constants with appropriate names

private static readonly double someConstant = 22.0;
// remaining constants

providing comments or full documentation on their meaning