“Taking a look at the last 10 years, history would tend to suggest that the markets do record outsized returns over this period,” Mr Oliver said.

“Over the 10 years to 2017, the average gain in US shares over the period has been about 1 per cent, and the US market has been up seven years out of 10.

“The pattern is even more pronounced in Australia, with average gains in the order of 2 per cent and the market up in eight of those 10 periods.”

Mr Oliver said 2018 had been a partial outlier to this theory, as markets had been weak up to Christmas Eve and had then rallied just before New Year, particularly in the US.

“So, in hindsight, Santa did deliver last year; he just landed a little later than usual,” Mr Oliver said.

He explained that several factors tended to drive sharemarkets up over Christmas, particularly reinvestment by US investors after they had sold shares before the end of the US financial year in September, and investment of Christmas bonuses.

“As we edge closer to Christmas, there are usually fewer IPOs and capital raisings, but investors are usually feeling a little more optimistic coming into the end of the year and searching for options to increase their holdings,” Mr Oliver said.

“That dynamic, combined with the investment of Christmas bonuses, can contribute to an influx of capital over the Christmas–New Year period.

“The record isn’t perfect, but history is usually on the side of investors receiving a Christmas present in the form of another Santa rally before the end of the year.”