By Katie Marsal

Published: 06:45 PM EST

Apple's two largest New York City retail stores are now known to be some of the town's largest retail cash cows, with the 5th Avenue flagship alone having drawn in $440 million in one year.

Upon looking at prospectuses showing the value of various properties in New York City's most important shopping district, the New York Post discovered the iconic store's extremely high yearly revenue and noted that it was much higher than some other stores along 5th Avenue. Clothing boutique chain Zara's store just a few blocks south, for example, is believed to take in 'just' $25 million per year.

Location is said to play a significant part for the store, which is located directly at the corner of Central Park, but isn't regarded as the only factor. Apple's SoHo store is located much further south in Manhattan but still collected $100 million in annual revenue, or four times the clothier's performance. Tourism is thought to contribute to the large the difference between the two Apple locations.

Details are unavailable for the West 14th Street store.

The figures were collected last year but hint that the Mac maker's largest stores provide a disproportionately large amount of its retail income, a ratio supported by a CNET investigation of recently opened stores elsewhere. Santa Barbara, California's just-opened State Street store is predicted to net $20 million in revenue per year as a single-floor shop in a less prominent city. Other predictions or past results are more difficult to obtain as Apple is known to fiercely guard any retail data that would let outsiders break down its sales at a per-store level.

Combined with the continuing increases in foot traffic from year-to-year at Apple's stores, word of such massive amounts of revenue leaves little surprise as to why the company is vowing large-scale makeovers of its existing stores and still plans to add 25 stores in fiscal 2009 at a time when established electronics chains have folded or put a freeze on expansion. Additional, optimized retail space has to date quickly translated into more customers, particularly in those areas where no official stores had existed before.

To that extent, Apple has already said that roughly half of the 25 new stores planned for fiscal 2009 are intended for non-US locations. Unofficially, these are known to include multiple first stores in major but previously unserved cities.