## Historical Consumer Price Index for All Urban Consumers (CPI-U)

All dollar amounts in IPUMS-Higher Ed are nominal dollars--that is, they are expressed in historical monetary terms and are not comparable between surveyed years due to inflation (or deflation). For example, $1 in 2009 is worth much less than $1 in 1962. The IPUMS-Higher Ed variable CPI2009C provides an easy way to adjust dollar amounts to constant dollars in 2009 for variables that has a reference year of the survey year (SALARY). Similarly, CPI2009P provides conversion for variables whose reference year is the previous year (EARN and HHINC). These conversion variables, constant within years, inflate or deflate dollar amounts to the amount they would have represented in 2009--as shown in Table 1 and Table 2.

**Table 1: Using CPI2009C to Convert Dollar Amounts in SALARY to Constant 2009 Dollars**

HIGHERED Data Year |
Income Year |
X |
CPI2009C |
= |
2009 dollars |

1993 | 1993 dollars | X | 1.485 | = | 2009 dollars |

1995 | 1995 dollars | X | 1.408 | = | 2009 dollars |

1997 | 1997 dollars | X | 1.337 | = | 2009 dollars |

1999 | 1999 dollars | X | 1.288 | = | 2009 dollars |

2001 | 2001 dollars | X | 1.211 | = | 2009 dollars |

2003 | 2003 dollars | X | 1.166 | = | 2009 dollars |

2006 | 2006 dollars | X | 1.064 | = | 2009 dollars |

2008 | 2008 dollars | X | 0.996 | = | 2009 dollars |

2010 | 2010 dollars | X | 0.984 | = | 2009 dollars |

2013 | 2013 dollars | X | 0.921 | = | 2009 dollars |

**Table 2: Using CPI2009P to Convert Dollar Amounts in EARN and HHINC to Constant 2009 Dollars**

HIGHERED Data Year |
Income Year |
X |
CPI2009P |
= |
2009 dollars |

1995 | 1994 dollars | X | 1.448 | = | 2009 dollars |

1997 | 1996 dollars | X | 1.367 | = | 2009 dollars |

1999 | 1998 dollars | X | 1.316 | = | 2009 dollars |

The 2009 base year was chosen simply for convenience. Adjusting to some other year would yield identical correlations, regression coefficients, inequality measures, and the like. After using CPI2009C or CPI2009P to convert nominal dollars to 2009 dollars, users who desire another base year for simple descriptive statistics can easily adjust 2009 dollars to 1939 dollars, 1949 dollars, or any other year by making use of the alternate factors provided in Table 3.

**Table 3: Converting Constant 2009 Dollars to Constant Dollars For Another Base Year**

2009 dollars |
X |
Alternate Factor |
= |
Income Year |

2009 dollars | X | 0.141 | = | 1962 dollars |

2009 dollars | X | 0.143 | = | 1963 dollars |

2009 dollars | X | 0.144 | = | 1964 dollars |

2009 dollars | X | 0.147 | = | 1965 dollars |

2009 dollars | X | 0.151 | = | 1966 dollars |

2009 dollars | X | 0.156 | = | 1967 dollars |

2009 dollars | X | 0.162 | = | 1968 dollars |

2009 dollars | X | 0.171 | = | 1969 dollars |

2009 dollars | X | 0.181 | = | 1970 dollars |

2009 dollars | X | 0.189 | = | 1971 dollars |

2009 dollars | X | 0.195 | = | 1972 dollars |

2009 dollars | X | 0.207 | = | 1973 dollars |

2009 dollars | X | 0.230 | = | 1974 dollars |

2009 dollars | X | 0.251 | = | 1975 dollars |

2009 dollars | X | 0.265 | = | 1976 dollars |

2009 dollars | X | 0.282 | = | 1977 dollars |

2009 dollars | X | 0.304 | = | 1978 dollars |

2009 dollars | X | 0.338 | = | 1979 dollars |

2009 dollars | X | 0.384 | = | 1980 dollars |

2009 dollars | X | 0.424 | = | 1981 dollars |

2009 dollars | X | 0.450 | = | 1982 dollars |

2009 dollars | X | 0.464 | = | 1983 dollars |

2009 dollars | X | 0.484 | = | 1984 dollars |

2009 dollars | X | 0.502 | = | 1985 dollars |

2009 dollars | X | 0.511 | = | 1986 dollars |

2009 dollars | X | 0.530 | = | 1987 dollars |

2009 dollars | X | 0.551 | = | 1988 dollars |

2009 dollars | X | 0.578 | = | 1989 dollars |

2009 dollars | X | 0.609 | = | 1990 dollars |

2009 dollars | X | 0.635 | = | 1991 dollars |

2009 dollars | X | 0.654 | = | 1992 dollars |

2009 dollars | X | 0.674 | = | 1993 dollars |

2009 dollars | X | 0.691 | = | 1994 dollars |

2009 dollars | X | 0.710 | = | 1995 dollars |

2009 dollars | X | 0.731 | = | 1996 dollars |

2009 dollars | X | 0.748 | = | 1997 dollars |

2009 dollars | X | 0.760 | = | 1998 dollars |

2009 dollars | X | 0.777 | = | 1999 dollars |

2009 dollars | X | 0.803 | = | 2000 dollars |

2009 dollars | X | 0.825 | = | 2001 dollars |

2009 dollars | X | 0.839 | = | 2002 dollars |

2009 dollars | X | 0.858 | = | 2003 dollars |

2009 dollars | X | 0.881 | = | 2004 dollars |

2009 dollars | X | 0.910 | = | 2005 dollars |

2009 dollars | X | 0.940 | = | 2006 dollars |

2009 dollars | X | 0.966 | = | 2007 dollars |

2009 dollars | X | 1.004 | = | 2008 dollars |

2009 dollars | X | 1 | = | 2009 dollars |

2009 dollars | X | 1.016 | = | 2010 dollars |

2009 dollars | X | 1.048 | = | 2011 dollars |

2009 dollars | X | 1.070 | = | 2012 dollars |

2009 dollars | X | 1.086 | = | 2013 dollars |

2009 dollars | X | 1.103 | = | 2014 dollars |