0 is merely a convenient numerical value that also has business meaning - no growth. You can then contrast any numerical value with this, 10% meaning it grew by

0 is merely a convenient numerical value that also has business meaning - no growth. You can then contrast any numerical value with this, 10% meaning it grew by a fraction of .1, and so on. For most percentage quantities, it usually makes sense to start at 0 if that has some business meaning.