PROPETRO HLDG CORP

Ticker: PUMP CUSIP: 74347M108 Class: Common Stock

ESSEX INVESTMENT MANAGEMENT CO LLC's Holding History (CIK: 0000201772)

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

Q3 2018

Shares 93,687 Value ($000) $1,545 Avg Close $16.12 Range $14.32 - $17.89

Q2 2018

Shares 96,098 Value ($000) $1,507 Avg Close $17.21 Range $14.00 - $20.91

Q1 2018

Shares 96,580 Value ($000) $1,535 Avg Close $18.08 Range $14.56 - $22.88

Q4 2017

Shares 99,265 Value ($000) $2,001 Avg Close $16.95 Range $13.26 - $20.60

Period	Shares	Value ($000)	Average Close	Price Range
Q3 2018	93,687	$1,545	$16.12	$14.32 - $17.89
Q2 2018	96,098	$1,507	$17.21	$14.00 - $20.91
Q1 2018	96,580	$1,535	$18.08	$14.56 - $22.88
Q4 2017	99,265	$2,001	$16.95	$13.26 - $20.60