The key is usually - I've been saying that all along. However the word was picked carefully - and it's meaning is "whatever level you are comfortable with" - you are making a sacrifice from your personal income - and that's the scope of the word in POG. (In contrast to making up our own use of the word).
Your overall financial standing helps bring context to your giving. I tend to think all these BiblePay specific terms for technical terms that already is a turn off to newcomers.
Mark 12:41-44 English Standard Version (ESV)
The Widow's Offering
41 And he sat down opposite the treasury and watched the people putting money into the offering box. Many rich people put in large sums. 42 And a poor widow came and put in two small copper coins, which make a penny.[a] 43 And he called his disciples to him and said to them, Truly, I say to you, this poor widow has put in more than all those who are contributing to the offering box. 44 For they all contributed out of their abundance, but she out of her poverty has put in everything she had, all she had to live on.