[Boost-users] [multi-index] looking for "not greater than"

Hello, I've got a container with an ordered non-unique key. I have to find an element, which is not greater than X. [1, 3, 3, 5, 7] myIndex.not_greater_than(4) --> 5 myIndex.not_greatet_than(7) --> 7 myIndex.not_greatet_than(8) --> 7 IUUC, neither lower_bound(), nor upper_bound() can help here. Is there a simple way to do this? Thanks.