DAWSON GEOPHYSICAL CO

CUSIP: 239359102 Class: CMN

GLENMEDE TRUST CO NA's Holding History (CIK: 0000314949)

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

Q2 2013
Shares 157 Value ($000) $5 Avg Close — Range —
Q3 2008
Shares 17,501 Value ($000) $817 Avg Close — Range —
Q2 2008
Shares 21,867 Value ($000) $1,300 Avg Close — Range —
Q1 2008
Shares 3,164 Value ($000) $213 Avg Close — Range —
Q3 2007
Shares 4,499 Value ($000) $348 Avg Close — Range —