Changes in PISA sample social class composition by books-in-the-home group, U.S. and six comparison countries, 2003–2009 (percentage points)
| Canada | Finland | Korea | France | Germany | U.K. | U.S. | |
|---|---|---|---|---|---|---|---|
| Group 1 (Lowest) | +2 | +1 | -1 | +6 | +5 | +5 | +7 |
| Group 2 | +2 | -2 | -2 | +1 | 0 | +2 | +2 |
| Group 3 | +1 | -3 | -2 | -3 | -1 | -1 | -3 |
| Group 4 | -1 | +1 | -2 | -2 | -2 | 0 | -3 |
| Group 5 | -1 | +4 | +4 | 0 | -1 | -3 | -2 |
| Group 6 (Highest) | -3 | 0 | +3 | -1 | -2 | -2 | -2 |
| Disadvantaged (Groups 1 and 2) | +4 | -1 | -3 | +6 | +5 | +7 | +10 |
| Middle class (Groups 3 and 4) | 0 | -2 | -4 | -5 | -3 | -1 | -6 |
| Advantaged (Groups 5 and 6) | -4 | +3 | +6 | -1 | -3 | -5 | -4 |
Source: Authors' analysis of OECD Program for International Student Assessment (PISA) 2000 and 2009 databases for each country, with authors' interpolations for 2000 social class composition to match 2009 books-in-the-home groupings