How to configure and track key metrics like MTTA and MTTR

Hi,

How to configure and track key metrics like MTTA (Mean Time to Acknowledge), MTTR (Mean Time to Resolution), Ticket Lifetime and MTTR / Ticket Lifetime excluding pending time.

How can we measure ticket lifetime minus pending time?

Can anyone guide on what has to be done to achieve;
1) Mean time to acknowledge (MTTA) on incidents & case
2) Mean time to Resolution (MTTR) including and excluding on-hold time (on incidents & case)

Thanks,
Sugand