Diamonds Index of price 1973-2001 Diamonds Index of price 1973-2001
| Year | 1 carat | ½ carat |
| 1973 | 100 | 100 |
| 1974 | 134 | 107 |
| 1975 | 132 | 104 |
| 1976 | 132 | 107 |
| 1977 | 155 | 128 |
| 1978 | 228 | 185 |
| 1979 | 366 | 254 |
| 1980 | 637 | 403 |
| 1981 | 377 | 299 |
| 1982 | 228 | 222 |
| 1983 | 207 | 208 |
| 1984 | 186 | 197 |
| 1985 | 166 | 183 |
| 1986 | 178 | 186 |
| 1987 | 199 | 194 |
| 1988 | 228 | 220 |
| 1989 | 245 | 249 |
| 1990 | 248 | 261 |
| 1991 | 246 | 262 |
| 1992 | 247 | 263 |
| 1993 | 249 | 265 |
| 1994 | 252 | 267 |
| 1995 | 254 | 266 |
| 1996 | 266 | 270 |
1997 |
276 |
274 |
1998 |
278 |
274 |