Between 1870 and 1940 the collection grew rapidly, from 17,000 to 941,500.
By the 1960s, the collection had grown to 800,000 books.
Since then, the collection has grown to more than 20,000 items.
By this date, the collection had grown to include 8,051 books.
The collection at the museum grew to around 600 pieces by 1998.
The museum's collection had grown to more than 900 pieces in 2009.
By 2007 the collection had grown to over 5,000 pieces.
Since then the collection has grown to over 800 objects.
He uses them every day; his collection grew to almost 30.
The collection has grown to over 400 pieces since that time.