MKS INSTRS INC

Ticker: MKSI CUSIP: 55306N104 Class: EQTY

GREAT WEST LIFE ASSURANCE CO /CAN/'s Holding History (CIK: 0001046192)

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

Q4 2025

Shares 38,169 Value ($000) $6 Avg Close $148.21 Range $120.73 - $170.37

Q3 2025

Shares 55,242 Value ($000) $7 Avg Close $106.31 Range $88.17 - $132.24

Q2 2025

Shares 55,559 Value ($000) $6 Avg Close $80.86 Range $54.50 - $100.44

Q1 2025

Shares 55,831 Value ($000) $4 Avg Close $100.21 Range $75.89 - $124.28

Q4 2024

Shares 83,312 Value ($000) $9 Avg Close $106.91 Range $96.54 - $118.37

Q3 2024

Shares 57,862 Value ($000) $6 Avg Close $117.45 Range $99.10 - $145.63

Q2 2024

Shares 53,734 Value ($000) $7 Avg Close $124.55 Range $105.72 - $137.52

Q1 2024

Shares 46,575 Value ($000) $6 Avg Close $114.51 Range $94.23 - $132.85

Q4 2023

Shares 46,206 Value ($000) $5 Avg Close $79.84 Range $62.28 - $104.49

Q3 2023

Shares 47,551 Value ($000) $4 Avg Close $95.58 Range $81.25 - $107.67

Q2 2023

Shares 41,967 Value ($000) $5 Avg Close $89.53 Range $77.81 - $108.20

Q1 2023

Shares 46,405 Value ($000) $4 Avg Close $93.12 Range $80.00 - $111.27

Q4 2022

Shares 46,720 Value ($000) $4 Avg Close $78.00 Range $62.97 - $89.22

Q3 2022

Shares 38,069 Value ($000) $3,142 Avg Close $100.01 Range $79.23 - $120.27

Q2 2022

Shares 34,377 Value ($000) $3,528 Avg Close $112.92 Range $94.75 - $148.07

Q1 2022

Shares 30,251 Value ($000) $4,664 Avg Close $150.35 Range $131.30 - $175.09

Q4 2021

Shares 28,085 Value ($000) $4,890 Avg Close $151.09 Range $136.06 - $172.80

Q3 2021

Shares 26,201 Value ($000) $3,985 Avg Close $148.13 Range $133.76 - $168.78

Q2 2021

Shares 21,589 Value ($000) $3,842 Avg Close $175.09 Range $158.98 - $192.11

Q1 2021

Shares 21,539 Value ($000) $3,989 Avg Close $161.78 Range $138.78 - $185.00

Q4 2020

Shares 38,686 Value ($000) $5,823 Avg Close $125.75 Range $101.82 - $152.08

Q3 2020

Shares 33,824 Value ($000) $3,694 Avg Close $112.47 Range $97.77 - $124.64

Q2 2020

Shares 34,931 Value ($000) $3,951 Avg Close $95.31 Range $70.45 - $112.06

Q1 2020

Shares 36,263 Value ($000) $2,950 Avg Close $97.84 Range $64.00 - $116.86

Q4 2019

Shares 36,499 Value ($000) $3,984 Avg Close $99.99 Range $81.07 - $109.78

Q3 2019

Shares 37,657 Value ($000) $3,478 Avg Close $78.64 Range $68.69 - $91.29

Q2 2019

Shares 58,328 Value ($000) $4,543 Avg Close $80.27 Range $67.03 - $98.53

Q1 2019

Shares 47,879 Value ($000) $4,446 Avg Close $76.40 Range $59.36 - $88.91

Q4 2018

Shares 47,528 Value ($000) $2,924 Avg Close $68.31 Range $53.35 - $77.61

Q3 2018

Shares 41,921 Value ($000) $3,365 Avg Close $86.11 Range $74.38 - $97.19

Q2 2018

Shares 37,577 Value ($000) $3,595 Avg Close $102.60 Range $86.55 - $115.42

Q1 2018

Shares 32,132 Value ($000) $3,716 Avg Close $103.13 Range $88.32 - $120.60

Q4 2017

Shares 31,512 Value ($000) $2,975 Avg Close $93.43 Range $82.69 - $103.63

Q3 2017

Shares 74,219 Value ($000) $6,979 Avg Close $76.52 Range $62.45 - $89.48

Q2 2017

Shares 79,170 Value ($000) $5,324 Avg Close $70.74 Range $60.40 - $82.65

Q1 2017

Shares 76,063 Value ($000) $5,228 Avg Close $61.31 Range $54.85 - $65.67

Q4 2016

Shares 71,318 Value ($000) $4,234 Avg Close $50.13 Range $43.15 - $57.04

Q3 2016

Shares 72,560 Value ($000) $3,606 Avg Close $43.66 Range $38.22 - $50.60

Q2 2016

Shares 67,934 Value ($000) $2,923 Avg Close $35.80 Range $32.24 - $39.81

Q1 2016

Shares 4,692 Value ($000) $176 Avg Close $31.35 Range $28.08 - $35.11

Q4 2015

Shares 4,692 Value ($000) $169 Avg Close $32.52 Range $26.43 - $35.02

Q3 2015

Shares 4,692 Value ($000) $158 Avg Close $31.60 Range $28.82 - $34.92

Q2 2015

Shares 4,692 Value ($000) $178 Avg Close $32.93 Range $29.54 - $35.95

Q1 2015

Shares 4,692 Value ($000) $158 Avg Close $31.63 Range $29.59 - $33.22

Q4 2014

Shares 4,692 Value ($000) $171 Avg Close $31.69 Range $27.30 - $33.99

Q3 2014

Shares 2,629 Value ($000) $88 Avg Close $29.19 Range $27.47 - $31.20

Q2 2014

Shares 2,629 Value ($000) $82 Avg Close $25.69 Range $23.72 - $27.88

Q1 2014

Shares 2,629 Value ($000) $78 Avg Close $26.46 Range $25.10 - $28.61

Q4 2013

Shares 2,629 Value ($000) $79 Avg Close $25.51 Range $23.10 - $27.14

Period	Shares	Value ($000)	Average Close	Price Range
Q4 2025	38,169	$6	$148.21	$120.73 - $170.37
Q3 2025	55,242	$7	$106.31	$88.17 - $132.24
Q2 2025	55,559	$6	$80.86	$54.50 - $100.44
Q1 2025	55,831	$4	$100.21	$75.89 - $124.28
Q4 2024	83,312	$9	$106.91	$96.54 - $118.37
Q3 2024	57,862	$6	$117.45	$99.10 - $145.63
Q2 2024	53,734	$7	$124.55	$105.72 - $137.52
Q1 2024	46,575	$6	$114.51	$94.23 - $132.85
Q4 2023	46,206	$5	$79.84	$62.28 - $104.49
Q3 2023	47,551	$4	$95.58	$81.25 - $107.67
Q2 2023	41,967	$5	$89.53	$77.81 - $108.20
Q1 2023	46,405	$4	$93.12	$80.00 - $111.27
Q4 2022	46,720	$4	$78.00	$62.97 - $89.22
Q3 2022	38,069	$3,142	$100.01	$79.23 - $120.27
Q2 2022	34,377	$3,528	$112.92	$94.75 - $148.07
Q1 2022	30,251	$4,664	$150.35	$131.30 - $175.09
Q4 2021	28,085	$4,890	$151.09	$136.06 - $172.80
Q3 2021	26,201	$3,985	$148.13	$133.76 - $168.78
Q2 2021	21,589	$3,842	$175.09	$158.98 - $192.11
Q1 2021	21,539	$3,989	$161.78	$138.78 - $185.00
Q4 2020	38,686	$5,823	$125.75	$101.82 - $152.08
Q3 2020	33,824	$3,694	$112.47	$97.77 - $124.64
Q2 2020	34,931	$3,951	$95.31	$70.45 - $112.06
Q1 2020	36,263	$2,950	$97.84	$64.00 - $116.86
Q4 2019	36,499	$3,984	$99.99	$81.07 - $109.78
Q3 2019	37,657	$3,478	$78.64	$68.69 - $91.29
Q2 2019	58,328	$4,543	$80.27	$67.03 - $98.53
Q1 2019	47,879	$4,446	$76.40	$59.36 - $88.91
Q4 2018	47,528	$2,924	$68.31	$53.35 - $77.61
Q3 2018	41,921	$3,365	$86.11	$74.38 - $97.19
Q2 2018	37,577	$3,595	$102.60	$86.55 - $115.42
Q1 2018	32,132	$3,716	$103.13	$88.32 - $120.60
Q4 2017	31,512	$2,975	$93.43	$82.69 - $103.63
Q3 2017	74,219	$6,979	$76.52	$62.45 - $89.48
Q2 2017	79,170	$5,324	$70.74	$60.40 - $82.65
Q1 2017	76,063	$5,228	$61.31	$54.85 - $65.67
Q4 2016	71,318	$4,234	$50.13	$43.15 - $57.04
Q3 2016	72,560	$3,606	$43.66	$38.22 - $50.60
Q2 2016	67,934	$2,923	$35.80	$32.24 - $39.81
Q1 2016	4,692	$176	$31.35	$28.08 - $35.11
Q4 2015	4,692	$169	$32.52	$26.43 - $35.02
Q3 2015	4,692	$158	$31.60	$28.82 - $34.92
Q2 2015	4,692	$178	$32.93	$29.54 - $35.95
Q1 2015	4,692	$158	$31.63	$29.59 - $33.22
Q4 2014	4,692	$171	$31.69	$27.30 - $33.99
Q3 2014	2,629	$88	$29.19	$27.47 - $31.20
Q2 2014	2,629	$82	$25.69	$23.72 - $27.88
Q1 2014	2,629	$78	$26.46	$25.10 - $28.61
Q4 2013	2,629	$79	$25.51	$23.10 - $27.14