DAWSON GEOPHYSICAL CO

CUSIP: 239359102 Class: CMN

GREAT LAKES ADVISORS, LLC's Holding History (CIK: 0001078013)

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

Q4 2014
Shares 231,700 Value ($000) $2,834 Avg Close — Range —
Q3 2014
Shares 343,274 Value ($000) $6,241 Avg Close — Range —
Q2 2014
Shares 169,822 Value ($000) $4,865 Avg Close — Range —
Q1 2014
Shares 174,982 Value ($000) $4,901 Avg Close — Range —
Q4 2013
Shares 60,550 Value ($000) $2,048 Avg Close — Range —
Q3 2013
Shares 33,072 Value ($000) $1,074 Avg Close — Range —
Q2 2013
Shares 25,424 Value ($000) $936 Avg Close — Range —