DAWSON GEOPHYSICAL CO NEW

Ticker: DWSN CUSIP: 239360100 Class: COM

SIMPLEX TRADING, LLC's Holding History (CIK: 0001488542)

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

Q4 2018

Shares 1,913 Value ($000) $6 Avg Close $4.06 Range $2.60 - $5.61

Q3 2018

Shares 538 Value ($000) $3 Avg Close $5.63 Range $4.70 - $7.07

Q1 2018

Shares 165 Value ($000) $1 Avg Close $5.01 Range $3.96 - $5.79

Q2 2017

Shares 1,938 Value ($000) $7 Avg Close $3.74 Range $3.07 - $4.56

Q1 2017

Shares 2,906 Value ($000) $16 Avg Close $5.89 Range $4.30 - $6.95

Q4 2016

Shares 375 Value ($000) $3 Avg Close $6.15 Range $5.10 - $7.32

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2018	1,913	$6	$4.06	$2.60 - $5.61
Q3 2018	538	$3	$5.63	$4.70 - $7.07
Q1 2018	165	$1	$5.01	$3.96 - $5.79
Q2 2017	1,938	$7	$3.74	$3.07 - $4.56
Q1 2017	2,906	$16	$5.89	$4.30 - $6.95
Q4 2016	375	$3	$6.15	$5.10 - $7.32