It is very rare to hear of such returns in other markets. (investorideas.com)
The motive for such a return is not of course that they may be expected to support the further development of science, but simply the recognition that they are true. (faith.org.uk)
I read somewhere that 25 - 30 % is considered very good but in today's economy I don't know how to expect such a return. (money.stackexchange.com)