UWP to GDP

[Pyromancer]

In the old, old "Trillion Credit Squadron", there is a formula that tells you how much a planet can spend on its space fleet. It mostly depends on the population, and is slightly modified by government type and whether the planet is on a war footing or not. Is there a better formula, that also takes the tech level into account? The best thing would be a formula to calculate the GDP from UWP. How much of that GDP is spent on the fleet could then depend on other factors.

 

[AnotherDilbert]

CT Striker has a slightly more detailed formula based on TL.

Note that the GDP calculations in neither TCS nor Striker are considered canonical, they are superseded by considerably lower GDP calculations in later editions.

 

[Reynard]

Pocket Empires (T4) had extensive formulation on world revenue and expenses that help determine how much could be spent on their ships and fleets. Imperial Squadrons was a companion that made the number more abstract for a strategic lever space game but it also gave one a better grasp of what building and maintaining squadrons and fleets entailed.

 

[Pyromancer]

The formula in Striker is helpful. I think I will build a mixture of that one and the one in TCS and calibrate it to today's buying power. That would be good enough, I think. But just out of curiosity, where can I find current, canonical GDP calculations? Are they in any Mongoose product, or do I have to look into T5? Or even GURPS Traveller?

 

[Reynard]

T5 uses a modified and more simplistic version of determining Resource Units from Pocket Empires. There's no real formulation beyond a measure of relative wealth and resource to compare worlds in T5. You could use the T5 RU system with Pocket Empire or Imperial Squadrons to create squadrons and fleets and might extrapolate to economy in Mongoose.

 

[Pyromancer]

How much money does the planet spend on its space fleet?

1) Calculate GDP
Base GDP x any applicable trade code modifier x total population

TL: Base GDP per capita in Cr
0: 0
1: 500
2: 1,000
3: 2,000
4: 4,000
5: 8,000
6: 16,000
7: 32,000
8: 64,000
9: 120,000
A: 200,000
B: 350,000
C: 500,000
D: 750,000
E: 1,000,000
F: 2,000,000

Tradecode: GDP modifier
Ag: 1.1
As: 0.5
De: 0.7
Hi: 1.2
Lo: 0.7
Li: 0.8
Ga: 1.5
Ic: 0.8
In: 1.1
Na: 0.9
Ni: 0.9
Po: 0.8
Ri: 1.2
Oc: 0.9
Va: 0.6

2) The percentage of GDP spend on the space fleet depends on government type and starport type, and whether there is peace or war.

Percentage spend on fleet = peace/war % x starport modifier

Government type: Peace %/War %
0: .4/1.5
1: .8/1.4
2: 1/1.5
3: .9/1.2
4: .85/1.45
5: .95/1.4
8: 1.1/1.2
9: 1.15/1.2
A: 1.2/1.5
B: 1.1/1.2
C: 1.2/1.5
D: 0.75/1.5

Starport type: Percentage modifier
A: 1
B: .9
C: .8
D: .7
E: .6

Example:
Jeffesth B9EA784-6 Li Oc, currently at peace

GDP = 350,000 x 0.8 x 0.9 x 10,000,000 = 2.52e12 Cr
Percentage spend on fleet: 1.1% x .9 = 0.99%

Cr spent on fleet = 25,000 MCr

 

[AnotherDilbert]

Example: Mora A-A99AC7-F Hi In Cs

GDP = 2 000 000 × 1,2 × 1,1 × 10 000 000 000 = 26 400 000 000 000 000 = 26 400 TCr.

Economy: The economic output (gross product) of this polity is estimated at 138,935,068 (BCr) (...almost 139 quadrillion credits).

http://wiki.travellerrpg.com/Third_Imperium#C._Polity_Quick_Facts:_1116

According to canon the entire Imperium has a GDP of 138 935 TCr. Any single system cannot have remotely as much as GDP as 26 400 TCr.

The average GDP/capita of the Imperium is around 7700 Cr. Even high tech systems cannot have a GDP/capita of more than about 10 000 Cr. If you care about canon, of course.

 

[Pyromancer]

Example: Mora A-A99AC7-F Hi In Cs

GDP = 2 000 000 × 1,2 × 1,1 × 10 000 000 000 = 26 400 000 000 000 000 = 26 400 TCr.

Economy: The economic output (gross product) of this polity is estimated at 138,935,068 (BCr) (...almost 139 quadrillion credits).

http://wiki.travellerrpg.com/Third_Imperium#C._Polity_Quick_Facts:_1116

According to canon the entire Imperium has a GDP of 138 935 TCr. Any single system cannot have remotely as much as GDP as 26 400 TCr.

The average GDP/capita of the Imperium is around 7700 Cr. Even high tech systems cannot have a GDP/capita of more than about 10 000 Cr. If you care about canon, of course.

You are right, my calibration was way off. So, new try:

Starting point is today's USA, with a GDP of around 50,000 $ per capita. If we convert 10 $ = 1 Cr, that's 5,000 Cr per capita.
Let's also assume that the USA is TL7 and Ri, In, Ga, that leads to a base GDP of around 2000 Cr per capita. (I also slightly increased the modifiers for In and Ni).

The new tables:

TL: Base GDP per capita in Cr
0: 0
1: 25
2: 50
3: 100
4: 250
5: 500
6: 1,000
7: 2,000
8: 3,000
9: 4,000
10: 6,000
11: 8,000
12: 10,000
13: 12,000
14: 14,000
15: 16,000

Tradecode: GDP modifier
Ag: 1.1
As: 0.5
De: 0.7
Hi: 1.2
Lo: 0.7
Li: 0.8
Ga: 1.5
Ic: 0.8
In: 1.2 (was: 1.1)
Na: 0.9
Ni: 0.8 (was: 0.9)
Po: 0.8
Ri: 1.2
Oc: 0.9
Va: 0.6

With those numbers, I get a total GDP for the 3I of 186 684 Trillion Credits - that's pretty close to the official 138 935 TCr.

But what would you do different?

 

[AnotherDilbert]

But what would you do different?

That is closer, but still ~35% high.

The comparison with current economies is difficult, I fear the Imperium is just poorer than the developed world today. I think the official comparison is CrImp 1 = $1 (1970). That would make CrImp 1 ≈ $2 - 4 (2015).

Increasing the modifiers is probably a good idea, today economies vary wildly in size even for fairly comparable countries.

I would set a higher value than 0 for TL 0, even a stone age economy produces something even if it only artisanal.

I would make the table increase by a fixed percentage for each TL, instead of a fixed number. So instead of +2000 for each TL, I would make it +20% for each TL.

Perhaps something like this?

TL      GDP/cap   
 0          1
 1          7
 2         73
 3        147
 4        294
 5        587
 6       1174
 7       2349
 8       2936
 9       3670
10       4588
11       5734
12       7168
13       8960
14      11200
15      14000

I decreased the GDP by 20% for each TL below 15, 50% for each TL below 7, and 90% for each TL below 2.
By a quick estimate it should give a result reasonably close to the official number (possibly a little high?).

 

[Pyromancer]

Ok, new numbers:
Base GDP roughly doubles per TL until TL 8, then roughly increases by 20% per TL:

TL: Base GDP
0: 10,
1: 25,
2: 50,
3:100,
4:200,
5:400,
6:800,
7:1600,
8:3000,
9:3600,
10:4300,
11:5200,
12:6200,
13:7500,
14:9000,
15:10800

And the modifiers based on trade codes vary more:
"Ag": 1.2,
"As": 0.5,
"De": 0.7,
"Hi": 1.4,
"Lo": 0.6,
"Ga": 1.75,
"Ic": 0.8,
"In": 1.3,
"Na": 0.8,
"Ni": 0.7,
"Po": 0.5,
"Ri": 1.5,
"Oc": 0.8,
"Va": 0.6

With those numbers, I get a total GDP of 147 261 Trillion Credits, that's well within the margin of error the Imperium itself has to deal with.

 

[Pyromancer]

This also means that the conflict ridden subsector I am building for a campaign will see a lot less capital ship action than I initially thought. They just can't afford them. Another excuse to design a few warships in the few thousand ton range myself.

 

[AnotherDilbert]

With those numbers, I get a total GDP of 147 261 Trillion Credits, that's well within the margin of error the Imperium itself has to deal with.

Looks good!

This also means that the conflict ridden subsector I am building for a campaign will see a lot less capital ship action than I initially thought. They just can't afford them. Another excuse to design a few warships in the few thousand ton range myself.

Seems even better!

 

[EldritchFire]

If I may ask, Pyromancer, where did you come up with these figures? Are they extrapolated from a prior edition

I love what you've come up with, and am looking forward to using them to in a home-made setting using Traveller!

Also, what are the percentages for government types 6 & 7, and starport X?

 

[Rikki Tikki Traveller]

I would recommend adding some variability. As written every world with the same UWP would have the same GDP, no matter what.

Maybe a standard 2D variation to the basic GDP number?

2 -50%
3 -40%
4 -30%
5 -20%
6 -10%
7 +0%
8 +10%
9 +20%
10 +30%
11 +40%
12 +50%

Overall, it keeps the averages the same (so it doesn't affect the Imperial totals); but for smaller settings, would give some variation...

Also, I think the changes in GDP based on tech level shouldn't be linear. I expect a Step Change at TL4 (industrial Revolution), TL9 (Gravitics and FTL) and TL 12 (Micro-Gravitics) another one probably exists at TL16 or 17 (AntiMatter).

 

[Pyromancer]

If I may ask, Pyromancer, where did you come up with these figures? Are they extrapolated from a prior edition

The GDP calculation is based on the one in Striker. There, it's base GDP (dependant on TL) times population, modified by trade code, but the numbers are different and much higher. The percentage spend on the fleet is taken from TCS and only slightly modified.

Also, what are the percentages for government types 6 & 7, and starport X?

Government 6 is captured government, the percentage is as high as the captor's.
Government 7 is balkanized. There, you take the government type of every faction.
(This is exactly as in TCS)

And regarding starport X: No starport, no starfleet (i.e. multiply by zero).

I would recommend adding some variability. As written every world with the same UWP would have the same GDP, no matter what.

Maybe a standard 2D variation to the basic GDP number?

...

Overall, it keeps the averages the same (so it doesn't affect the Imperial totals); but for smaller settings, would give some variation...

Good idea.

Also, I think the changes in GDP based on tech level shouldn't be linear. I expect a Step Change at TL4 (industrial Revolution), TL9 (Gravitics and FTL) and TL 12 (Micro-Gravitics) another one probably exists at TL16 or 17 (AntiMatter).

The change is not linear, but exponential, and I like it that way.
(In Striker, it was linear, starting with 2,000 at TL5 and increasing by 2,000 per TL)

 

[EldritchFire]

If I may ask, Pyromancer, where did you come up with these figures? Are they extrapolated from a prior edition

The GDP calculation is based on the one in Striker. There, it's base GDP (dependant on TL) times population, modified by trade code, but the numbers are different and much higher. The percentage spend on the fleet is taken from TCS and only slightly modified.

Cool.

Also, what are the percentages for government types 6 & 7, and starport X?

Government 6 is captured government, the percentage is as high as the captor's.
Government 7 is balkanized. There, you take the government type of every faction.
(This is exactly as in TCS)

And regarding starport X: No starport, no starfleet (i.e. multiply by zero).

With Gov't 7, then, you just use the percentage from whatever the 'parent' government is?

How do you figure out info for a balkanized planet, though? Divide the population into however many governments are on the planet, then figure each out individually? Use the Faction Strength table to eyeball the percentage of the population in each government type, or assume each is of roughly equal strength since much smaller governments would have been subsumed into the bigger ones?

And I figured that Starport X was x0, but wasn't sure if they could outsource the construction/maintenance to a friendly system.

 

[Pyromancer]

How do you figure out info for a balkanized planet, though? Divide the population into however many governments are on the planet, then figure each out individually? Use the Faction Strength table to eyeball the percentage of the population in each government type, or assume each is of roughly equal strength since much smaller governments would have been subsumed into the bigger ones?

You have to come up with something yourself. I haven't thought about it.

 

[dmccoy1693]

This is really neat. I just ran the numbers of the major powers (and a few likely soon-to-be-conquered worlds) to see what their respective space fleets would be like. DAMN!!!! I can really see how Malforge and Cornath are major powers in Fessor Subsector and should be feared by the smaller worlds.

The People's Militia of Malforge has a space fleet budget of MCr. 3,300 (which includes a sizable lowering to the people of Zafinn since they are a captured world and are not yet back up to full production),
The Cornathian Empire's space fleet is MCr. 709, and
Fessor has a budget of MCr. 56,000.

Compare that to Kinth, an independent system with J-1 of the PMM, that has a budget of Cr. 40,000.

 

[atpollard]

This is really great stuff ... exactly what I was looking for (I needed GWP for a sandbox PbP game and was getting a headache thinking about trying to convert the Pocket Empires RU's into standard Credits.)

 

[AnotherDilbert]

Government type: Peace %/War %
0: .4/1.5
1: .8/1.4
2: 1/1.5
3: .9/1.2
4: .85/1.45
5: .95/1.4
8: 1.1/1.2
9: 1.15/1.2
A: 1.2/1.5
B: 1.1/1.2
C: 1.2/1.5
D: 0.75/1.5

This table is from TCS and is not a percentage, but a just a relative number.

Striker says:

B. Military Spending: The average expenditure of a nation or world on its military is 3% of its GNP; on worlds where the state of international tension is high, this may range as high as 15%; where little conflict has been experienced for extended periods of time the military budget may be as low as 1% of the GNP.
The total military budget must be divided between the army and the navy. The proportion allocated to the army averages 40% on most worlds, but averages only 6% on worlds with vacuum or trace atmospheres. Planetary defenses are jointly funded by the army and navy; the referee must decide what effect this will have on the army budget.

To get the Naval budget we need to multiply the value from this table by something like 0.5% (for a very calm neighbourhood) to 5% (for a region building up to a major war). Call it a Referee Modifier.

Naval Budget = GDP × GovMod × RefMod

Example: (New Home) Budget = 9000000000000 × 0,95 × 3% = Cr 256500000000 = GCr 256,5