This year saw strong stamp sales, with the highest sums reserved for more unusual issues - including Chinese and Russian stamps.

British Empire stamps were also popular, with an 1861 Perot Provisional cover providing a spectacular highlight in December.

While there was a downward trend in sales at the bottom end of the market, things remain buoyant at the top - with investors continuing to pay top dollar for high end stamps.

Top postage stamp sale of 2015

The stamp was withdrawn shortly after its release in 1968

The top stamp sale of 2015 was for a Chinese Whole Country is Red stamp, which realised $445,103 at InterAsia Auctions in July.

The stamp was issued in 1968 and quickly withdrawn after it was noticed that the contested island of Taiwan was coloured in white and a couple of archipelagos were missing.

A larger example of the issue sold for $1.1m in 2014.

2015's most important postage stamp sales

An 1861 Perot provisional cover was another highlight, with a final bid of $121,000 at Spink in December. It's one of few covers to display the first Bermudan provisional stamp.

The 1930 Italian royal wedding series was changed to an orange background

A 1930 Italian royal wedding block of four sold for $75,557 at Spink Geneva in January. It's the only known multiple of the issue, which was originally printed in sheets of 50.

A Kenya & Uganda £100 red and black was the star of a sale at Spink in January, achieving a £120,000 ($181,516) bid. It dates to the mid-1920s, before Kenya became a crown colony.

A pair of 1907 Nyasaland 2d stamps sold in November. The lot realised £22,000 ($33,130) in an auction at Spink.

The most unusual postage stamp sale of 2015

These Aegean stamps were issued by Italian administrators

These pro-assistance stamps were issued by Mussolini's forces on the occupied islands of the Aegean.

They were issued by Italian administrators during the Axis collaboration of the Greek archipelago during the second world war.

Only around 20 have made it to the present day, the majority in poor condition. This vertical pair made $35,560 at Spink in January.

It was a breakout year for…

2015 was not so much a breakout year as a continuation of the frenzied appreciation of the Golden Monkey issue in China.

While the lot is far from the rarest modern issue (it dates to the 1980s), it displays a popular design and is sought by collectors and non-collectors alike.

A sheet of 80 sold for $163,654 in February,

It was a year to forget for…

Stanley Gibbons , which saw its share price drop significantly this year.

One you may have missed

The Ulankom post office stood in a remote region of Mongolia

This Ulankom Russian post offices cover sold for $232,307 at Spink in January.

The lot was sent from Ulankom, Mongolia through the Russian postal system. It was the only letter ever sent through this office, which was opened a week before the October revolution and closed soon afterward.