ION GEOPHYSICAL CORP

CUSIP: 462044108 Class: COM

STRS OHIO's Holding History (CIK: 0000820478)

Note: Option positions (PUT/CALL) are excluded.

Q4 2015
Shares 220,800 Value ($000) $111 Avg Close — Range —
Q3 2015
Shares 220,800 Value ($000) $86 Avg Close — Range —
Q2 2015
Shares 220,800 Value ($000) $236 Avg Close — Range —
Q1 2015
Shares 205,200 Value ($000) $445 Avg Close — Range —
Q4 2014
Shares 210,400 Value ($000) $579 Avg Close — Range —
Q3 2014
Shares 210,400 Value ($000) $587 Avg Close — Range —
Q3 2013
Shares 55,160 Value ($000) $287 Avg Close — Range —
Q2 2013
Shares 67,600 Value ($000) $407 Avg Close — Range —