560 POUNDS x 7 DAYS (=1 week) x 4 WEEKS (=1 month) x 12 MONTHS (=1 year) x 25 YEARS
7x4 is only 28
I don't know about your months but my months don't usually have 28 days.
I would use 560 x 30 days x 12 months x 25 years because most months have 30-31 days. loving february
also the above is equal to 5 040 000 .. so the people who wrote the article are still dumb either way