Most of the great art of the world is being kept in museum and gallery storage. Public galleries and museums have been displaying art to the public since the 17th century for society’s benefit. But many of the world’s best artworks are not actually on display.

Quartz Media surveyed 20 museums in seven different countries, focusing on 13 major artists, and discovered that in some cases, more of the artist’s works were in storage and not on display.

The survey looked at some of the world’s largest museums including the Metropolitan Museum of Art in New York and Saint Petersburg’s Hermitage Museum.

It is reported that a large museum will display, on average, just five per cent of their collection at a time. The rest of their collection is kept in their archives.

Much of the art in museums has been donated by artists, collectors or foundations. Museums are one of the most reliable places to store important works of art with proper conservation practices to encourage preservation. For that reason, much of the art in museum archives isn’t actually for public viewing, unless the donator has specified otherwise.

Other works of art that may have been intended for display require more frequent preservation to ensure their longevity and can therefore not be on display for long, or at all.