More that one fifth to charity

Is there a way one would be allowed to donate more than one fifth of his income to charity?

Dear …,

Despite the fact that the Sages indeed said that one should not give more that one fifth of one’s income to charity, there are several ways that one is allowed to give more.

1. To support Torah learning.
2. An extremely wealthy person can give more than fifth.
3. On his deathbed, a person can distribute one third or even one half of his property.
4. If paupers ask one for charity, one is allowed, and it’s actually a very pious deed, to give more that one fifth.
5. Someone who wastes his money on excesses and luxury can give more.
6. If one will not become broke by giving more than a fifth – for example, if one gives just a little bit more.
7. If one gives so as to atone for his sins.

Source: Shulchan Aruch, Yoreh De'ah 249:1