I just looked it up, and apparently health care costs for pets has gone up in price even faster than for humans.

Pets typically don't have medical insurance, and any insurance that does exist there has a radically different regulatory regime than for humans.

Since 1980 for the US:

CPI has gone up by 3.16% on average per year (x4.17 in total). Human healthcare costs by 4.9% per year (x8.96 in total). And pet healthcare costs by 6.49% (or x17.87 in total).