When Cessna was still building 150/152s, the flight schools "retired" their 150s and replaced them with newer models every few years. They ended up in private ownerships with relatively low time. When Cessna stopped building the 152s in 1985, the flight schools didn't have anything to replace them with, so they keep using the 152s in their fleets. That's why the 152s usually have higher time. My '80 152 has around 9400 hrs now.

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