anchor: For example, if the analysis indicated that the maximum feasible level for 1998 was at or closer to one of the lower prior year standards than it was to the 1997 standard, prescribing that lower standard would not necessarily be impermissible.
positive: if the analysis indicated that the maximum level was lower prior to last years standards prescribing that lower standard would not necessarily be impermissible.
negative: if the analysis indicated that the maximum level was lower prior to last years standards prescribing that lower standard would be impermissible.