One factor which is often forgotten, is that the 'number' of doctors/GPs is one thing- the number of hours they work, is another.
It was the norm in the 60s/70s for Junior doctors to work over 120 hrs per week -now it is 70 on call and 52 (from top of head)- so can you imagine how many more doctors you need just to cover this. GPs also used to work 70 + hours and then have all the admin of the 'business' to do, insurance reports that take forever, etc, etc- and used to do home visits and night-cover- on average 1 night in 3 or 4, on top of a full working day, not instead of. They no longer do so, and many GPs choose to work part time - eg part-time of the shorter working hours. No-one, let alone the Government, is taking this into account in the figures.