Last Day of the Month Subscription

Does anyone have a way to set up a Subscription for the last day of the
month?
We've been changing reports so they only have data on the last day of the
month, but the report also needs to run on demand and return data.
There must be a way.
Thanks,
MikeSo far, I have not found a simple way to do this (thanks Microsoft for
leaving out the obvious). Interestingly MSDN and Technet both have articles
that say you can run a report 'on the last day of the month' but never
provide details. I have to run my report on the last day of the month...it
cannot be on the first day (which is easy).
My first thought had been to set it to run on 31st for all months and
perhaps Reporting Services is smart enough to figure out that there aren't 31
days in a particular month...but I am afraid that it simply won't fire on
these months...
The only solution I have come up (but not tested) with requires creating 3
separate subscriptions and setting them to run on the last day of specific
months (check only the months you want that version of the subscription to
run).
28 -29 - Feb (uses a range - would probably generate an extra report in
those years with 29 days in Feb...)
30 - April, June, Sept, Nov
31 - Jan, March, May, July, Aug, Oct, Dec