We dinna ken athoot rael census data, but footerin wi Excel an an the Census data we hae, A doot ye can jist aboot jalouse the follaein:
(a) There muckle mair Scots speakers noo nor at the time o the Union.
(b) The tap o speaker nummers wis maist like aroon the turn o the 19/20t centuries, mibbie as monie as twa an a hauf million fowk.
(c) Scots speakers cud weel hae bin in the majoritie in Scotland as late as the 1940s.
Nae idea o onie wark backin this up 😉 but interestin feegurs aw the same.
1721 Map of Scotland