Mondrian inflation

B262 sold at Sotheby's, New York in May 2002 for $5.3M.

The installation photograph, right, from CR shows B262 at the Modern Pictures for Modern Rooms exhibition, London, April 1936. Photographer unknown.

Interestingly, the catalogue gives a price of £40 (and the same for B263). £40 to £3.6M in 66 years. I learned here that a Leica 111 f2 Summar sold for £39.10.0 in that year: the top of the range Leica non-digital rangefinder, the M7 with 50mm f2 Summicron-M now costs around £4,100. A post on that link suggests that an agricutural labourer's wages would have been around £1.12.0 (£1.50) per week at the time. The minumum adult (>21) wage is currently (2011) £5.93 per hour, £208 for a 35 hour week, 75 years later.
In round terms: Mondrians have risen by a factor of 90,000 in 66 years; Leicas by 100; and minimum wage by 140 in 75 years. So it goes - please advise me of any factual or mathematical errors encountered in these paragraphs.