Bit of a blonde moment there Risky.
In comp, gold rank My Tank queue time is 2-5 seconds.
Dps and support queue time is 120-300 seconds.
Dps queues are 24 to 150 times longer. You could say theres 24 to 150 times more dps/support players than there are tank.
Its not exact no, but still thats alarming.
Most of those 13% of remaining tank players are in qp. Possibly many of those are just people doing weeklies.