10 % of 0

Since this situation comes up, I will put forth a scenario. If a member had a good job, and tithed well over 10% for a long time, if he/she loses that job would he/she be allowed not to tithe, since 10% of 0 = 0?   Or would that person be allowed to tithe less if he/she eventually got a job that paid less?  Does anybody know or have an idea of how that is handled?  Does a person lose status somewhat if they are not tithing, or not tithing as much as they once were? 

I am just wondering because it seems as though they have no choice.  I know of a person who tried to pull back on tithes because the spouse talked about it with him/her and they together agreed it had to be less.   The pastor met with that person, and the member was told the tithe had to go back up to the original level "for spiritual growth."  This caused so much stress and trouble in that marriage.  It was as if the non-member had no say in about financial issues in his/her own marriage.