There was one other good news in 2017 report. Also this can only be calculated indirectly:
There were app. 96 approved applications and 92k of issued visa. With a rough estimation, that app. 40% of all applicants did not need visa for Canada (because they already had some other type of visa), I would estimate app. 129k of all approved applicants.
That would give the average family size less than 1.4 for the family size. And that is including PNP, where family size tends to be bigger.
That is actually the only thing saving the ITA in 3k+ range. Would it be higher (1.7 to 1.9), they would need less ITA (since total waste rate is much lower now).