NORTHWESTERN CORP

Ticker: NWE CUSIP: 668074305 Class: EQTY

NATIXIS ADVISORS, L.P.'s Holding History (CIK: 0001018331)

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

Q4 2017

Shares 70,502 Value ($000) $4,209 Avg Close $42.54 Range $39.78 - $45.45

Q3 2017

Shares 84,200 Value ($000) $4,794 Avg Close $41.74 Range $40.09 - $43.18

Q2 2017

Shares 84,805 Value ($000) $5,174 Avg Close $42.35 Range $40.29 - $44.62

Q1 2017

Shares 89,044 Value ($000) $5,227 Avg Close $39.52 Range $38.19 - $41.05

Q4 2016

Shares 107,146 Value ($000) $6,094 Avg Close $38.33 Range $36.64 - $40.23

Q3 2016

Shares 106,707 Value ($000) $6,139 Avg Close $40.31 Range $38.22 - $43.00

Q2 2016

Shares 125,401 Value ($000) $7,910 Avg Close $39.68 Range $37.02 - $42.70

Q1 2016

Shares 145,004 Value ($000) $8,954 Avg Close $38.33 Range $34.60 - $41.62

Q4 2015

Shares 162,630 Value ($000) $8,822 Avg Close $35.84 Range $33.71 - $37.52

Q2 2015

Shares 11,559 Value ($000) $564 Avg Close $33.40 Range $31.54 - $35.25

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2017	70,502	$4,209	$42.54	$39.78 - $45.45
Q3 2017	84,200	$4,794	$41.74	$40.09 - $43.18
Q2 2017	84,805	$5,174	$42.35	$40.29 - $44.62
Q1 2017	89,044	$5,227	$39.52	$38.19 - $41.05
Q4 2016	107,146	$6,094	$38.33	$36.64 - $40.23
Q3 2016	106,707	$6,139	$40.31	$38.22 - $43.00
Q2 2016	125,401	$7,910	$39.68	$37.02 - $42.70
Q1 2016	145,004	$8,954	$38.33	$34.60 - $41.62
Q4 2015	162,630	$8,822	$35.84	$33.71 - $37.52
Q2 2015	11,559	$564	$33.40	$31.54 - $35.25