what is a s and p ptp index participation rate

The closing price for the S&P 500 (GSPC) yesterday was $6,405.49. It was down 0.6% for the day (down 0.7% from previous close).

DATE OPEN HIGH LOW CLOSE VOLUME
August 19 2025 19:00
$6,405.49
$6,405.49
$6,405.49
$6,405.49
August 19 2025 18:30
$6,406.10
$6,407.60
$6,401.92
$6,406.32
124,733,000
August 19 2025 17:30
$6,412.61
$6,416.23
$6,404.23
$6,406.16
235,240,000
August 19 2025 16:30
$6,418.58
$6,420.66
$6,403.39
$6,412.68
269,172,000
August 19 2025 15:30
$6,430.95
$6,434.09
$6,416.23
$6,418.58
261,833,000
August 19 2025 14:30
$6,444.99
$6,450.27
$6,420.66
$6,430.94
401,392,797
August 19 2025 13:30
$6,446.24
$6,456.48
$6,435.47
$6,445.21
535,611,791
Daily pricing data for the S&P 500 dates back to 12/30/1927, and may be incomplete.