In Manhattan there are many variables in determining the price differential for each floor. A beautifully renovated apartment on a lower floor can sell for a higher price than an "original condition" apartment on a high floor.
The parlor floor in a townhouse may be worth more than the 4th floor if it's a walk-up. A 10th floor apartment facing the back will sell for less than the same apartment on the 5th floor directly facing Central Park.
Unless the building owns the air rights over neighboring buildings, views can and will change in Manhattan. A high floor facing an interior courtyard doesn't have as nice a view as the corner apartment on a low floor overlooking the park. Higher floors usually have a premium as do views. Both premiums can be separate. A view can be subjective. However, kitchens and bathrooms can be replaced but there is only one Central Park and Hudson river in Manhattan.
When pricing or determining value of a Manhattan condo or coop it is crucial to compare apples to apples. All coops and condos in Manhattan have an offering plan.
In the original offering plan whether new construction or conversion, the developer/sponsor put a price differential for each floor and unit in the building.
The sponsor determined premiums for each unit. Since all offering plans are from different years and during different market conditions there is a premium percentage for every attribute. In a coop, premiums for attributes are also allocated with more shares in the corporation.
Think in terms of percentages rather than arbitrary dollar amounts.
For example, if you're considering purchasing or selling in a building that was built or converted in the 80's, you can figure out the approximate percent of the premium.
If the same apartment, line, and square footage was selling in the $200,000 range originally and today the same apartments are selling in the $800,000 range, the apartment today is worth 4x more. If they're selling in the million dollar range 5x.
The premium for floor differential is 4x more whatever it was in the offering plan. If it was $2000 per floor in the offering plan, than it would be around $8000 per floor today providing the comparable apartments are otherwise the same. Price per share (in a coop) and price per square foot can also be used as evaluation tools. However, all square footage is not equal.
In today's transparent information age there are many online tools or "gimmicks" designed for automated instant home values. Take them all with a grain of salt. An algorithm looks at data logically. Real estate data isn't always logical. Selling and buying real estate is emotional not logical.
In Manhattan pricing a home is as much an art as a science.
Pricing a home is a marketing function, the price you get is a function of the marketing you choose.