How much is a 2 liter bottle of soda in 1995?

Answer 1

Assuming this is an inflation problem, you can use the consumer price index (CPI) to estimate.

The CPI is a measure of consumer prices compared to a base year value, usually the price in 1982.

CPIn / 100 = (Price in year n / Price in 1982)

The CPI for 2010 is ~218. The CPI for 1995 is ~152. The CPI for 1982 is 100 by definition (hence why we divide the CPI by 100). A 2L of coke is approximately $2.25 from a cursory search over the internet. Therefore

2.18 = (2.25 / price in 1982)

Price in 1982 = 1.03

1.52 = (price in 1995 / 1.03)

$1.56 = Price in 1995

CPI are published by the department of labor and are available at ftp://ftp.bls.gov/pub/special.requests/cpi/cpiai.txt

obviously sub in any more relevant data you have