I wasn't intending to quote reported. I apologize if I gave the wrong impression in that regard. I was basing it on total reported operating cost divided by reported available seat miles.
Now that it's clear that there's a discrepancy between the two, it appears that I'm including some extra stuff. According to the 10K, here's what I included in "total operating cost":
[numbers are in millions]
Personnel: $2,662
Fuel: $830
Express Capacity Purchases: $645
A/C rent: $431
Other rent & landing fees: $429
Selling expenses: $407
A/C maintenance: $402
D&A: $232
Asset Impairments: $34
Government Compensation: ($214) [this is a credit]
Other operating expense: $1,239
Total operating expense: $7,097
Total ASM: 51,564,717,500 (not in millions)
Based on their reported 11.36c, that would mean taking everything in the above cost list except for "other operating expense." Their reported RASM excludes freight; I included freight in my calculations.
The hard part here is making an apples-to-apples comparison. If I use WN's method, I get the 13c CASM. If I use US's method, WN's numbers no longer match their annual reports, because of the exclusion of freight from revenue and "other" from cost. So I guess it all depends on what sort of metrics one is using when referring to these numbers.