NORTHWESTERN CORP

Ticker: NWE CUSIP: 668074305 Class: EQTY

VAUGHAN NELSON INVESTMENT MANAGEMENT, L.P.'s Holding History (CIK: 0001021642)

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

Q4 2017

Shares 779,825 Value ($000) $46,556 Avg Close $42.54 Range $39.78 - $45.45

Q3 2017

Shares 959,250 Value ($000) $54,620 Avg Close $41.74 Range $40.09 - $43.18

Q2 2017

Shares 947,600 Value ($000) $57,823 Avg Close $42.35 Range $40.29 - $44.62

Q1 2017

Shares 963,925 Value ($000) $56,582 Avg Close $39.52 Range $38.19 - $41.05

Q4 2016

Shares 1,139,425 Value ($000) $64,799 Avg Close $38.33 Range $36.64 - $40.23

Q3 2016

Shares 1,063,150 Value ($000) $61,163 Avg Close $40.31 Range $38.22 - $43.00

Q2 2016

Shares 1,223,675 Value ($000) $77,177 Avg Close $39.68 Range $37.02 - $42.70

Q1 2016

Shares 1,429,750 Value ($000) $88,287 Avg Close $38.33 Range $34.60 - $41.62

Q4 2015

Shares 1,588,375 Value ($000) $86,170 Avg Close $35.84 Range $33.71 - $37.52

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2017	779,825	$46,556	$42.54	$39.78 - $45.45
Q3 2017	959,250	$54,620	$41.74	$40.09 - $43.18
Q2 2017	947,600	$57,823	$42.35	$40.29 - $44.62
Q1 2017	963,925	$56,582	$39.52	$38.19 - $41.05
Q4 2016	1,139,425	$64,799	$38.33	$36.64 - $40.23
Q3 2016	1,063,150	$61,163	$40.31	$38.22 - $43.00
Q2 2016	1,223,675	$77,177	$39.68	$37.02 - $42.70
Q1 2016	1,429,750	$88,287	$38.33	$34.60 - $41.62
Q4 2015	1,588,375	$86,170	$35.84	$33.71 - $37.52