@Legoisthebest
I remember when the Boxing Day Sales were actually January Sales. Gave the staff a bit more time to organise price changes.
Yep, there was never any such thing as 'Boxing Day Sales.' the post-Christmas Sales' were the 'January Sales.....'
I may be misremembering but I am sure there was only one main 'sale' in the shops pre 1990s. The January Sales. They were HUGE and people used to queue up for 2 or 3 days to get TVs, and stereos, and even mink coats for a fraction of the price. Literally like 70-80% off. Not off everything, but off a few BIG sticker items, and there'd be 4 or 5 of each. If the sale was 2nd January, some people used to pitch a tent, and camp out from the afternoon of the 31st December.
Then there used to be a smaller, mid-summer (or end-of-summer) sale when shops wanted to get rid of the Spring/Summer clothing lines and suchlike. And that was it I think.
Now there seems to be sales every other bloody week. One big one is the dreadful 'Black Friday Sales.' (Started in the UK about a decade ago.) It used to be one day, then it was 'Black Friday weekend,' and THEN it was 'Black Friday week,' and THEN it became Black Friday bloody fortnight. THIS year it was Black Friday MONTH. 
Ludicrous. As I said, there are sales all year round now, and 80-90% of the stuff is shit they have had for several years, and can't get rid of!