the Mosquito had proven itself 4.95 times more cost-efficient than the Lancaster.
I don't know where that figure comes from off the top of my head, nor how it was calculated.
In terms of the man power cost of bombing, A Lancaster consumed 9.5 man months per 1000 lbs of bombs delivered, compared to 16 man months for the Mosquito. This was the measure used by the BBSU and, by it, the Lancaster was a far more cost effective delivery system.
The strategic bombing campaign could not have been carried out by the Mosquito, which
generally carried 2,000 lbs of bombs over typical ranges (until the introduction of types capable of carrying 4,000 lbs). It would have required thousands of aircraft.
In 1943 the weight in short tons dropped by the Lancaster and Mosquito respectively were 112,600 and 1,736.
In 1944 the weight in short tons dropped by the Lancaster and Mosquito respectively were 404,300 and 16,980.
In 1945 the weight in short tons dropped by the Lancaster and Mosquito respectively were 152,00 and 11,120.
The most destructive munitions carried by any aircraft of Bomber Command were incendiary. The Mosquito could and did carry incendiary loads, but it was not specialised in or noted for this role.
Bowyer probably summed up the effect of Mosquitoes of the Light Night Striking Force when he wrote of its first year of operations.
"Losses during autumn 1943 on nuisance attacks represented 1.75% of sorties flown. Set against this was the fact that not much material damage resulted from Mosquito raids, but clearly they confused defences and were valuable because the interruption they caused was out of all proportion to the expenditure of effort."
These raids, sometimes dropping target indicators rather than high explosives or other incendiaries were something the Mosquito was really good for. Despite the low losses, in the period around the end of 1943 and into 1944 nearly 50% of Mosquito sorties received some damage from flak, thankfully usually light, and this is rarely factored into calculations of cost and efficiency.
Cheers
Steve