How RARE is it?

General Motors does not keep extremely copious notes when they produce cars. Especially if those cars could potentially be collector's items in the future due to rarity. On the previous page was all of the RPO codes of each option that was available on the 1988 Pontiac Trans AM GTA.

My particular GTA is already considered rare because of its exterior color, Gunmetal Metallic (RPO 87U), because there were only 930 total produced for purchase in the United States in 1988. What I have attempted to do is break it down even further to find out how many similar GTAs to mine were produced. These figures represent only those GTAs that were produced for purchase in the United States and do not include any GTA that was exported to Canada or Europe that year.

Of those 930 Gunmetal Metallic GTAs produced, not all had the same options. Some were t-top models. Some had the LB9 5.0L TPI V8 with either the TH700-R4 or T-5 five speed manual transmission. Finally, some had the standard gage cluster. How many came as a hardtop, 5.7L TPI V8 with TH700-R4, and the digital dash?

Let's try to figure out how rare my car is...

The major options on my car other than the exterior color are:

1. Hardtop Coupe
2. B2L / L98 5.7L Tune Port Injection V8
3. Electronic Dash and supporting equipment
4. Grey Cloth Interior

Some minor options on my car include:

1. 3.27:1 Gear Ratio w/Limited Slip Posi-trac
2. Almuminum Driveshaft

Alright, here is where the fun in mathematics begins...

7,234 - Hardtop Coupe models produced making 74.08% of 9,756 GTAs produced.
6,913 - B2L / L98 5.7L produced making 70.79% of 9,765 GTAs produced.
5,102 - Digital Dash models produced making 52.2% of 9,765 GTAs produced.
2717 - Grey Cloth Interior equipped models produced making 27.8% GTAs produced.

The minor options come out to 70.79% of 9,765 GTAs produced.

Let's break it down even further...

If you multiple the percentage of GTAs produced with the above options against the 930 Gunmetal Metallic GTAs produced then you come up with the following figures.

689 of 930 GTAs were Hardtop Coupes.
658 of 930 GTAs were 5.7L V8 equipped with 3.27:1 gears and aluminum driveshafts.
458 of 930 GTAs had the Digital Dash option.
258 of 930 GTAs came with Grey Cloth Interior.

Next, dividing those figures together brings a precentage of the 930 Gunmetal Metallic GTAs produced with those options.

689 of 930 = 74.08% (Hardtop Coupe)
658 of 930 = 70.75% (5.7L V8, 3.27:1 gears, and aluminum driveshaft)
458 of 930 = 49.2% (Digital Dash)
258 of 930 = 27.7% (Grey Cloth Interior)

With 258 being the lowest numbered option of 930, take the percentages for the remaining options and multiply those percentages into 258 to get the percentage of 258 Grey Cloth Interior GTAs that had the other options. That gives you:

191 of 258 = 74.03% (Hardtop Coupes)
182 of 258 = 70.5% (5.7L V8, 3.27:1 gears, and aluminum driveshaft)
127 of 258 = 49.2% (Digital Dash equipped)

With 127 being the lowest numbered option of 258, take the percentages for the remaining options and multiply those percentages into 127 to get the percentage of the 127 Grey Cloth Interior and Digital Dash equipped GTAs that had the other options. That gives you:

94 of 127 = 74.03% (Hardtop Coupe)
89 of 127 = 70.5% (5.7L V8, 3.27:1 gears, and aluminum driveshaft)

With 89 being the lowest numbered option of 127, take the percentages for the remaining options and multiply those percentages into 89 to get the percentage of the 89 Grey Cloth Interior, Digital Dash equipped, and Hardtop Coupe GTAs that had the 5.7L V8, 3.27:1 gears, and aluminum driveshaft. That gives you:

89 of 94 = 68% (Hardtop Coupes)

Multiplying 89 into 68% gives me an approximate number of how many 1988 Gunmetal Metallic GTAs are similar to mine. That number is...84...84 1988 Gunmetal Metallic Pontiac Trans AM GTAs. So it is estimated that there are only 83 other cars exactly like mine that were produced during the 1988 model year off the GTA assembly line at Van Nuys.

**These numbers are only estimates. General Motors did not break down production numbers like this when the cars were produced. This is a "best" guess of how many similar GTAs were produced during this model year and nothing more based on the production numbers obtained from the GTA Source Page.**
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Page 1: Introduction
Page 2: RPO and Technical Data
Page 3: How RARE is it?
Page 4: Photography of Vader...part one
Page 5: Photography of Vader...part two
Page 6: Photography of Vader...part three
Page 7: Vader's Heart
Page 8: Inside Vader
Page 9: Modifications, Upgrades, and Repair...part one
Page 10: Modifications, Upgrades, and Repair...part two
Page 11: Modifications, Upgrades, and Repair...part three
Page 12: Modifications, Upgrades, and Repair...part four
Page 13: Literature and Awards
Page 14: Car Shows and Events
Page 15: The Track and at Play
Page 16: My other Firebirds