Results from an annual poll conducted by Gallup shows that despite a huge increase per capita GDP in China since 1999, the Chinese people's sense of well-being or quality of life has remained more or less unchanged over the same time period. Gallup asked respondents to rate their lives on a 0 to 10 "ladder" based on the Cantril Self-Anchoring Striving Scale, in which respondents are told that the top of the ladder, 10, "represents the best possible life for you" and the bottom of the ladder, 0, "represents the worst possible life for you." As the graph (right) indicates, the average life rating in China has remained stable around 4.7 since 1999. The per capita GDP, on the other hand, has more than tripled since 1999, going from $2,152 to $7,536 in 2010. These results put China below most other countries surveyed in Eastern and Southeastern Asia, with an average life rating above only respondents in Mongolia and Cambodia. As the second chart shows (right), Singapore had the highest average life rating among these countries at 6.5. One possible reason wealth may have a negligible impact on life satisfaction in China - put forward by the Gallup article discussing these results - is that cultural norms and Confucian influence "lead Chinese people to avoid using material wealth as an appropriate basis for evaluating their lives."