Coverage results over the time (RTL)

Is it possible to track the coverage results over the time? For bug detection, it is well accepted that the rate at which bug are detected approximates an exponential decay. That is at beggining is should be easier to detect bug, then it becomes more an more complicate. We can distinguish between easy and hard-to-detect bugs. The trends can be depicted in this chart:

Bug detection
  ^
  |--------- 100% ------------------------------
  |                                    *    *   *
  |                              *
  |                       *
  |                *   
  |           *
  |       *   
  |    *                      
  |  *                        
  |*
  |-----------------------------------> Time

 Can I register toggle or block coverage at RTL with timing information for printing a similar chart?