Fix exponential inflation

[PikkaBird]

For those who don't quite understand the problem:

I'm making a road vehicle GRF and I create a vehicle called the "Plozzowow Rootburger", a coal truck which is used between 1980 and 2000.

To test it, I create a quick game starting in 1980, the year the vehicle is introduced. My tests show that the Rootburger earns about twice as much as its running costs; perfect! So all is well and I release the GRF.

Simone Nooby downloads my GRF and starts a game with it in the game year 1920. By the time her game reaches 1980 and the Rootburger is introduced, TTD's inflation model has eroded its earning capacity to the point that it barely breaks even. Simone tries to use Rootburgers, but after a while decides they're stupid and useless. She removes my GRF and goes back to the much cheaper default road vehicles.

Basil Proplayer wants to play a 19th century game. He loads up his sailing ships, his horse wagons, and the Rootburger. By the time the game gets to 1980, TTD's inflation model means the Rootburger - along with every other vehicle in the game - is haemorrhaging cash at a tremendous rate. Basil concludes that the game is broken and stops playing it.

Or what about putting 1950 (or 1900) as the standard and every year after 1950 has x% inflation and before x% deflation

While this would fix the problem of wildly different economies depending on start date, it would not fix the problem of wildly different economies with inflation on or off, particularly at dates a long way from the epoch. Inflation being purely cosmetic is the only sensible solution to this problem.

[Robbedem]

Would it be possible to ignore inflation for running and purchase costs from NewGRF, while keeping the inflation for the rest? (building tracks, default vehicles, funding industry, landscaping,...)

[Supercheese]

Would it be possible to ignore inflation for running and purchase costs from NewGRF, while keeping the inflation for the rest? (building tracks, default vehicles, funding industry, landscaping,...)

Theoretically, given enough mucking around with the source code. Not entirely sure why you'd want that, however.

[jonty-comp]

They's some sexy graphs.

[Jacko]

my best solution, whilst pointless for the point of this thread..
is to play with inflation off.

Though I remember once on TTD a looooooong time ago when it got so much i ended up with a negative Company value...lol

[Robbedem]

Would it be possible to ignore inflation for running and purchase costs from NewGRF, while keeping the inflation for the rest? (building tracks, default vehicles, funding industry, landscaping,...)

To be clear: I mean that the NewGRF running and purchase costs should be inflated like income, while everything else remains as it is.

Why do this?
This would solve the problem of balancing NewGRF's for games with inflation off or on.

[Hyronymus]

I have a brain wave after reading Robbedem's suggestion about pre and post 1950 calculation. How about making inflation a proportional exponent of the passed game years divided by the amount of years between 2050 (default end year) and the start year rather than the amount of passed years. To prevent unwanted effects from raising to the power of a fracture it can be expressed as a percentage. In short, instead of doing:

(inflation) = 1,1 ^ (amount of passed years)

do:
(inflation) = 1,1 ^ (((current game year counted from the start year) / (amount of game years from start year to 2050)) * 100)

[michael blunck]

[...]

Yeah, nothing new, you already pointed this out in 2011 (or before): http://www.tt-forums.net/viewtopic.php?p=971953#p971953

But even then, most vehicle set developers have always been aware of this problem. E.g., the DB Set had a warning message about this (that it needs "startyear 1921") from the beginning.

Like so many other problems, this one is due to extending temporal and spatial limits of the original game in OTTD. Maybe it´ll help making the inflation setting readable by newGRFs.

regards
Michael

[Robbedem]

I have a brain wave after reading Robbedem's suggestion about pre and post 1950 calculation. How about making inflation a proportional exponent of the passed game years divided by the amount of years between 2050 (default end year) and the start year rather than the amount of passed years. To prevent unwanted effects from raising to the power of a fracture it can be expressed as a percentage. In short, instead of doing:

(inflation) = 1,1 ^ (amount of passed years)

do:
(inflation) = 1,1 ^ (((current game year counted from the start year) / (amount of game years from start year to 2050)) * 100)

You mean 1,02 instead of 1,1?
While this would indeed be an improvement, there would still be a difference for games started early:
start 1800
in 1950 cost = x3.28
income = x1.82
-> ratio = 1.8

start 1900
in 1950 cost = x1.93
income = x1.39
-> ratio = 1.4

[Robbedem]

Srry for double post, but wanted to show this graph

from 1800 to 1900 there was almost no inflation, perhaps that would be a solution? Start inflation only from 1900.

[Eddi]

any chance you could provide this in a "useful" file format?

[PikkaBird]

I have a brain wave after reading Robbedem's suggestion about pre and post 1950 calculation.

If there's one thing I've learned from creating NARS2 and UKRS2, it's that complex calculations with subtle effects are a waste of time.

The choices are;

A) Have non-divergent inflation.
B) Have rebalanced, epoch-based divergent inflation, give newgrfs the ability to detect the inflation setting, and get newgrf authors to provide balanced vehicle statistics for both no inflation and divergent inflation.

B may be more satisfying from a theoretical point of view, especially if you're not the one that's going to have to code it. But the net effect of "no inflation divergence" and "inflation divergence, but newgrfs will compensate for it" is almost exactly the same. The only difference is that the latter creates a lot more unnecessary work for newgrf authors.

If NewGRF authors want vehicular costs to increase over time, of course, they can do that already, without relying on a one-size-fits-all built-in model. UKRS2 does this. But personally I think it's a bad idea, from a gameplay point of view.

[Eddi]

How about these suggestions:

1. Have a fixed inflation rate (4%-ish) and instead make the income/cost spread as a configurable long-term-difficulty setting (current 1% is really difficult, 0% would be "pure eye-candy" inflation, make up steps inbetween as you please)
2. Have the inflation based on a fixed base year, not the starting year, i.e. adjust prices on starting the economy (the starting/max loan will be adjusted by this factor as well)
3. make the current spread factor available to NewGRFs (as fixed-point number), so they can do whatever with it
4. start charging a sizable interest rate on the loan

[Robbedem]

any chance you could provide this in a "useful" file format?

How do you do that?

Here is an excel graph, this time for the US

[planetmaker]

How do you do that?

Images are best provided in a format which can be shown by a browser...

docx or xlsx instead require every user to download a file which is in a proprietary file format, is known to be a major trojan and virus carrier (I don't say your files contain any, but how do I know?), requires everyone to start yet another programme, and worst, the file formats are not made to display graphics.

[Robbedem]

Images are best provided in a format which can be shown by a browser...

I've done some searching, and apparently I need a website to store the pictures on first and then link to that site, right?
What website would you suggest?

[Eddi]

what's wrong with attaching the image to this forum, like you did with the other files?

[Arie-]

I've uploaded the file to Google Docs, it shows a graph diagram which is attatched. I have no idea what the values on the Y-axis represent, the X-axis seem to represent years AD.

[michael blunck]

I have no idea what the values on the Y-axis represent, the X-axis seem to represent years AD.

Looks like depletion in monetary value, probably for the U.K. See here: http://www.tt-forums.net/viewtopic.php?p=875793#p875793

regards
Michael

[Robbedem]

I have no idea what the values on the Y-axis represent, the X-axis seem to represent years AD.

Thanks Arie

The graph is based on info from the Federal Reserve of Minneapolis (USA)
The y-axis represents the annual average of the consumer price index.