How much does weight really affect the operation cost? Hi given an information from a reliable new source article (https://www.nytimes.com/2008/06/11/business/worldbusiness/11iht-air.1.13628276.html), it was mentioned that "Every 25 pounds we remove, we save $440,000 a year,". I wonder the validity of the statement because it goes against basic math. 

Here is what I got,

\$440,000/yr/25 lbs = $17,600/yr/lb

Let's say a passenger weight at 200 lbs, this means by removing one passenger out of the plane, an airline would save   $\dfrac{\$3.5 million}{year \ person}$. 

That means that one passenger should be paying more than that amount over the year, but if we think calculate that by using a ticket from L.A. to New York as an example, that's not the case (calculation shown below).

$ \dfrac{\$262}{person}$ $\times$  $\times$ $ \dfrac{4 flights}{day}$ $\times$ $ \dfrac{365 days}{year}$ = 
$\dfrac{\$380k}{year \ person}$

I know there must be something wrong in this simplistic calculation, but I couldn't figure out. I am hoping someone here could point that out (with a reference would be awesome). 

Thanks in advance.
A couple of old references behind paywalls estimate commercial aircraft weight reduction is worth $300-800/lb over the life of the aircraft, and it is heavily fuel price dependent. This was back when fuel was half the cost it is today, so double it.

Your reference quotes a Northwest Airlines manager who may have been describing savings across their whole fleet of 320 planes. This drops the annual savings to 50/lb/aircraft, or $1500/lb across the 30yr life of an aircraft, roughly equivalent to my two sources.