The Ratio of Physical versus Website Visitors to Museums

I lately joined the Museum Computer Group which has a very active discussion list, and a question was posed lately about how many physical visitors do museums get, versus website traffic these days. @Mia_out helpfully pointed to the UK's Department for Culture, Media and Sport's "Sponsored Museums: Performance Indicators 2010-11" which included downloadable spreadsheets of performance indicators like physical and web visitors at http://www.culture.gov.uk/what_we_do/research_and_statistics/8609.aspx.

Here I've quickly juxtaposed the total physical visits to museums sponsored by DCMS with their corresponding total web visits (there arent any more nuanced stats, before you ask). Although the ratio varies from museum to museum (check out the V+A! 8 times as many online visitors as physical visitors!) it just gives demonstrable proof of how important web presence is to cultural and heritage organisations.
Have a look (below, I'm having bother with blogger and tables...). Fascinating.

Institution	Total Physical Visits 2010-2011	Total Unique Web Visits 2010-2011	Ratio
British Museum	5,869,396	21,496,815	3.662526
Geffrye Museum	104,691	527,082	5.034645
Horniman Museum	584,974	252,867	0.43227
Imperial War Museum	2,317,639	8,587,082	3.705099
Museum of Science and Industry in Manchester	638,347	330,000	0.51696
National Gallery	5,084,929	4,500,000	0.884968
National Maritime Museum	2,450,155	10,052,347	4.102739
National Museums Liverpool	2,635,993	3,176,266	1.20496
National Museum of Science and Industry	4,093,463	15,020,206	3.669315
National Portrait Gallery	1,758,488	13,724,626	7.804788
Natural History Museum	4,812,197	7,397,821	1.537306
Royal Armouries	462,753	403,379	0.871694
Sir John Soane's Museum	109,604	365,099	3.331074
Tate Gallery	7,450,000	19,427,000	2.607651
Tyne and Wear Museums Service	2,018,233	1,006,250	0.49858
Victoria and Albert Museum	3,049,000	24,976,400	8.191669
Wallace Collection	357,538	305,609	0.854759
Total Visits	43,797,400	131,548,849	3.003577