I completely understand the frustration of "best of lists", and I can assure you that I read hundreds of comments here on the Yahoo Music blogs whenever we post one. Many times our "best album" lists generate thousands of comments. And although many of the remarks are ridiculous, many are valid in a subjective sort of way.

For this playlist I wanted to find the true top 20 albums once and for all, but to do this I needed to clear my mind of all opinion and approach it as a science. My own personal taste did not influence this list in any way. In fact, I would have made many different choices, but the time I put into collecting the data and crunching the numbers leaves no doubt in my mind that this is the most accurate top 20 album list in existence.

To begin with I had to set the parameters, and I have set them as follows:

1. The list is based on the American market - I did this only because I had mounds of detailed data on the American music market at hand- to include the whole world or even Europe would increase the complexity of the analysis greatly - So this is really the "Top 20 Albums of All Time (To Americans)"

2. "Greatest Hits" albums and live albums were not eligible. The idea here was to identify the very best true albums, not compilations that cherry pick the best songs from an artist's career.

3. The following mathematical formula was used:

"Album Staying Power Value + Sales Value + Critical Rating Value + Grammy Award Value"

Now if you wish to argue, I welcome intelligent comment on how to hone the formula further, but please try to control the passionate fan-speak that drives so many of the comments. Remember, the idea is to completely remove your personal opinion from the process.

To offer a bit more detail on the components of the formula:

The initial group of albums selected was based solely on sales. Please know that I believe sales alone are probably the worst measure we have of an album's quality and I will speak to how I addressed this problem in a few. But as a starting point sales made the most sense. Sales are by no means the only measure of a "great album", but without big sales an album doesn't have much footing on which to claim the moniker "greatest". A vote with a dollar is a much stronger indicator than any other.

I looked at the biggest selling albums of all time in America based on actual RIAA data - this produced 71 non-Greatest Hits/Live albums that have all sold over 10 million units. Any of these that sold more than 10 million units received a 1% Sales Multiplier for every 1 million units sold over 10 million.

Sales Value = Sales Multiplier X Staying Power Value

Next, I determined what the Staying Power Value (SPV) was of all 71 albums. To determine Staying Power Value I looked at used CD sales data to determine how well each album's value has held up over time. For example, in the secondary market you can expect to pay around $9.50 for a copy of Rumours by Fleetwood Mac, but you would only pay $1.38 for a copy of Cracked Rear View by Hootie and The Blowfish. The Staying Power Value is important because it shows what the current value of the album is in the marketplace. So it's a good reflection of supply and demand. Rumours sold 19 million copies and Cracked Rear View sold 16 million. Rumours gets more points for selling more units, but even more important than the higher overall sales figures is that people want to hold onto their Fleetwood Mac CD, but don't mind parting with their Hootie CD. SPV captures this. In simple terms, Staying Power Value reflects current supply and demand for each album. *Please note that for double albums we reduced the SPV to align with a standard-length album.

So if we take the previously mentioned SPV of Fleetwood Mac's Rumours album and multiply it by that album's Sales Multiplier of 9% (1% for each million sold over 10 million) we get $10.38. But this only shows us how much people still desire the album + how many have sold at retail.

The next part of the formula takes into account critical acclaim.

I would agree with anyone who says a critical review means nothing, but when you start to see a pattern among the critics the data becomes much more reliable. If ten out of ten reviewers give an album 5 stars chances are good that the album is a winner. Basically the more reviews you average the more reliable the rating.

For the Critical Rating Value I looked at multiple reviews for each album from a diverse cross section of music magazines, newspapers and music review websites to come up with the average review number for each based on a 5 star scale. From these ratings I assigned a Critical Rating Multiplier to each album ranging from 0% to 10%.

So now our formula has factored in critical acclaim making the end result more reliable.

Ratings Value = Sales Value X Rating Multiplier

The final portion of the formula is the Grammy Award Value and it simply looks at how many Grammy Awards each album has won. Our formula already has the voice of the people (Sales Value) and the voice of the critics (Critical Rating Value) so the only missing component is the acclaim each album holds among it's peers. The Grammys are an industry specific award and are the best reflection we have of how the music business itself feels about an album. I would agree that this is the least important of the components in our formula, and as such each Grammy award adds only a .5% bonus. So an album that wins 4 Grammys would receive an extra 2% to it's value. This in my estimation is a fair weighting to give for a Grammy award.

So now I give you The Top 20 Albums of All Time based purely on the analysis provided above and devoid of any personal opinion. If you would like to see the complete analysis you can download the Microsoft Excel version here: (Top Album Analysis.xls).

#20. Faith - George Michael
 Play Album
Year: 1987 Units Sold: 10 Million
SPV: $9.19 Rating (Stars): 4 Grammys Won: 1
Calculated value per unit based on the formula: $9.79

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#19. Appetite For Destruction - Guns N' Roses
 Play Album
Year: 1987 Units Sold: 15 Million
SPV: $8.81 Rating (Stars): 4 Grammys Won: 0
Calculated value per unit based on the formula: $9.81

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#18. Purple Rain - Prince
 Play Album
Year: 1984 Units Sold: 13 Million
SPV: $8.74 Rating (Stars): 4.75 Grammys Won: 2
Calculated value per unit based on the formula: $9.82

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#17. Houses Of The Holy - Led Zeppelin
 Play Album
Year: 1973 Units Sold: 11 Million
SPV: $9.10 Rating (Stars): 4.5 Grammys Won: 0
Calculated value per unit based on the formula: $9.93

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#16. Born In The U.S.A. - Bruce Springsteen
 Play Album
Year: 1984 Units Sold: 15 Million
SPV: $8.91 Rating (Stars): 5 Grammys Won: 0
Calculated value per unit based on the formula: $10.29

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#15. Nevermind - Nirvana
 Play Album
Year: 1991 Units Sold: 10 Million
SPV: $10.07 Rating (Stars): 4 Grammys Won: 0
Calculated value per unit based on the formula: $10.67

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#14. Van Halen - Van Halen
 Play Album
Year: 1978 Units Sold: 10 Million
SPV: $10.23 Rating (Stars): 4.25 Grammys Won: 0
Calculated value per unit based on the formula: $10.84

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#13. Rumours - Fleetwood Mac
 Play Album
Year: 1977 Units Sold: 19 Million
SPV: $9.52 Rating (Stars): 5 Grammys Won: 1
Calculated value per unit based on the formula: $11.47

.#12. The Wall - Pink Floyd
 Play Album
Year: 1979 Units Sold: 23 Million
SPV: $10.20 Rating (Stars): 4.75 Grammys Won: 1
Calculated value per unit based on the formula: $12.51.#11. The Joshua Tree - U2
 Play Album
Year: 1987 Units Sold: 10 Million
SPV: $11.50 Rating (Stars): 4.5 Grammys Won: 2
Calculated value per unit based on the formula: $12.54.#10.  Metallica - Metallica
 Play Album
Year: 1991 Units Sold: 14 Million
SPV: $12.08 Rating (Stars): 4.25 Grammys Won: 1
Calculated value per unit based on the formula: $13.38.#9. Led Zeppelin - Led Zeppelin
 Play Album
Year: 1969 Units Sold: 10 Million
SPV: $12.83 Rating (Stars): 4 Grammys Won: 0
Calculated value per unit based on the formula: $13.60.#8. Hotel California - Eagles
 Play Album
Year: 1976 Units Sold: 16 Million
SPV: $12.00 Rating (Stars): 4.75 Grammys Won: 0
Calculated value per unit based on the formula: $13.81.#7. The White Album - The Beatles
 Play Album
Year: 1968 Units Sold: 19 Million
SPV: $12.00 Rating (Stars): 5 Grammys Won: 0
Calculated value per unit based on the formula: $14.39.#6. Led Zeppelin IV - Led Zeppelin
 Play Album
Year: 1971 Units Sold: 23 Million
SPV: $12.42 Rating (Stars): 5 Grammys Won: 0
Calculated value per unit based on the formula: $15.44.#5. Abbey Road - The Beatles
 Play Album
Year: 1968 Units Sold: 12 Million
SPV: $14.94 Rating (Stars): 4.25 Grammys Won: 1
Calculated value per unit based on the formula: $16.23.#4. Physical Graffiti - Led Zeppelin
 Play Album
Year: 1975 Units Sold: 16 Million
SPV: $14.31 Rating (Stars): 4.75 Grammys Won: 0
Calculated value per unit based on the formula: $16.38.#3. Thriller - Michael Jackson
 Play Album
Year: 1982 Units Sold: 27 Million
SPV: $13.49 Rating (Stars): 4.5 Grammys Won: 4
Calculated value per unit based on the formula: $17.39.#2. Dark Side Of The Moon - Pink Floyd
 Play Album
Year: 1973 Units Sold: 15 Million
SPV: $16.08 Rating (Stars): 5 Grammys Won: 0
Calculated value per unit based on the formula: $18.57.#1. Songs In The Key Of Life - Stevie Wonder
 Play Album
Year: 1976 Units Sold: 10 Million
SPV: $16.84 Rating (Stars): 5 Grammys Won: 2
Calculated value per unit based on the formula: $18.71