Obedience to reason is the foundation of liberty. Reason banishes slavery of self to materialism, to political correctness, to folly, and to range-of-the-moment consciousness known best by the hedonist.
A number of factors can change this estimate, including: Astigmatism. Contact lenses that correct astigmatism cost more than soft contacts that only correct nearsightedness or farsightedness. Soft contact lenses for astigmatism, called toric contacts, frequently retail for $50 to $70 for a box of six lenses. So if you replace your toric contact lenses every two weeks, your annual lens cost is roughly $500 to $700.
You can do the same for astigmatism correction, though it only becomes relevant if the glasses astigmatism is at least -0.75 to -1 diopters (otherwise combine cylinder and spherical from the glasses prescription for the contact lens).