Quarterly spending on mobile game Candy Crush Saga fell steadily over the course of 2014, but its players still spent $1.33bn (£865.2m) on in-app purchases for the sweet-swapping hit.

Analysis by the Guardian of publisher King’s latest financial results, as well as previous filings, reveals that Candy Crush Saga’s “gross bookings” – the term used to cover spending by players – totalled $1.04bn in the second half of 2013.

That means $2.37bn of Candy Crush spending over the 18-month period. King did not separate out Candy Crush and non-Candy Crush revenues before that point, but with the game having launched in 2012, it’s almost certainly past $3bn of lifetime spending.

In terms of gross bookings, Candy Crush Saga peaked some time ago. Analysis of King’s financial filings, including presentations breaking out its non-Candy-Crush gross bookings, reveals a high point of $551m for that game alone in the third quarter of 2013.

It’s been downhill ever since: $493m of player spending in the final quarter of 2013, then $429.5m, $360.5m, $277.4m and $263.8m in the four quarters of 2014. Even so, it remains one of the most lucrative mobile games in the world.

Should King be worried about the declining revenues for its biggest hit? The company has been working hard to make up for the slide with its other “Saga” games, to reduce its reliance on Candy Crush Saga.

In the final quarter of 2013, the game accounted for 78% of King’s gross bookings, but a year later, it was just 45% – the first quarter in a long time that non-Candy Crush Saga spending made up the majority of spending on the company’s games.

So, while Candy Crush Saga spending nearly halved – it was down by 46.5% – between the final quarters of 2013 and 2014, spending on other King games was up 136.5% to $324m in the same period.

In the final quarter of 2014, King had 356 million monthly unique users – individuals playing one or more of its games – although only 8.3 million of them spent any money on them.

So, while 97.7% of people playing King’s games are playing for free, the 2.3% that pay are spending an average of $23.42 a month within the games – the metric of “monthly gross average bookings per paying user” (or MGABPPU in a sector of the games industry that loves an acronym) in King’s financial results.