question regarding this graph:

Category Sex 99th $280,000- $260,000 $240,000 - $220,000 - 98th $200,000- $180,000 - 97th $160,000 - 96th 95th $140,000 - $120,000 - 90th $100,000 - $80,000 75th $60,000 - 50th $40,000 - $20,000 - 25th 10th so- Male Female Total - Both sexes