SQL Server 2022

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CREATE TABLE fuel$ 
(
    year	INT,
    combined_mpg_ft1	float,
    tailpipe_co2_in_grams_mile_ft1 float,
    fuel_type_1 Varchar(50),
    Avg_MPG	float,
    CO2Avg_withoutEV float  
);

INSERT INTO fuel$  (year) VALUES
	('2017'),
	('2016'),
	('2015'),
	('2014'),
	('2013'),
	('2012'),
	('2011'),
	('2010'),
	('2009'),
	('2008'),
	('2007'),
	('2006'),
	('2005'),
	('2004'),
	('2003'),
	('2002'),
	('2001'),
	('2000'),
	('1999'),
	('1998'),
	('1997'),
	('1996'),
	('1995'),
	('1994'),
	('1993'),
	('1992'),
	('1991'),
	('1990'),
	('1989'),
	('1988'),
	('1987'),
	('1986'),
	('1985'),
	('1984');

CREATE TABLE Example 
(
    year	INT,
    Avg_MPG	float,
    CO2Avg_withoutEV float
);

INSERT INTO Example (year, Avg_MPG, CO2Avg_withoutEV) VALUES
	('2017', '23.3069727891156', '403.622448979592'),
	('2016', '23.2543068088597', '401.520098441345'),
	('2015', '22.9001597444089', '410.376198083067'),
	('2014', '22.4621212121212', '420.217171717172'),
	('2013', '22.1125541125541', '426.671861471861'),
	('2012', '21.2674315975287', '442.702780760987'),
	('2011', '20.6821844225604', '453.368674056042'),
	('2010', '20.5172727272727', '455.575235248908'),
	('2009', '19.6935483870968', '472.894285955177'),
	('2008', '19.2099494097808', '484.636291784655'),
	('2007', '18.9786856127886', '488.015485242184'),
	('2006', '18.9592391304348', '490.083167976901'),
	('2005', '19.1938250428816', '486.015500057546'),
	('2004', '19.0677361853832', '488.114786450446'),
	('2003', '18.9443911792905', '493.684013045447'),
	('2002', '19.087358684481', '488.743285382219'),
	('2001', '19.2461368653422', '484.083871743709'),
	('2000', '19.2954545454545', '482.456799430981'),
	('1999', '19.3656804733728', '482.362414669942'),
	('1998', '19.4289245982695', '481.056745493943'),
	('1997', '19.4291338582677', '482.244866706037'),
	('1996', '19.5847347994825', '479.560836009444'),
	('1995', '18.7973112719752', '502.192459531232'),
	('1994', '19.0122199592668', '494.883790328922'),
	('1993', '19.1043000914913', '494.837783902195'),
	('1992', '18.8626226583408', '502.228115497502'),
	('1991', '18.8259717314488', '504.270073251502'),
	('1990', '19.0009276437848', '499.800704041559'),
	('1989', '19.1257588898526', '499.143176756376'),
	('1988', '19.3283185840708', '493.083160108052'),
	('1987', '19.2285485164395', '499.584206543624'),
	('1986', '19.5504132231405', '490.45326128694'),
	('1985', '19.8083480305703', '487.146809266722'),
	('1984', '19.8818737270876', '489.237133709112');

UPDATE fuel$  SET fuel$.Avg_MPG=e.Avg_MPG, fuel$.CO2Avg_withoutEV=e.CO2Avg_withoutEV
FROM fuel$ f
INNER JOIN Example e on e.year=f.year

SELECT * FROM fuel$

year	combined_mpg_ft1	tailpipe_co2_in_grams_mile_ft1	fuel_type_1	Avg_MPG	CO2Avg_withoutEV
2017	null	null	null	23.3069727891156	403.622448979592
2016	null	null	null	23.2543068088597	401.520098441345
2015	null	null	null	22.9001597444089	410.376198083067
2014	null	null	null	22.4621212121212	420.217171717172
2013	null	null	null	22.1125541125541	426.671861471861
2012	null	null	null	21.2674315975287	442.702780760987
2011	null	null	null	20.6821844225604	453.368674056042
2010	null	null	null	20.5172727272727	455.575235248908
2009	null	null	null	19.6935483870968	472.894285955177
2008	null	null	null	19.2099494097808	484.636291784655
2007	null	null	null	18.9786856127886	488.015485242184
2006	null	null	null	18.9592391304348	490.083167976901
2005	null	null	null	19.1938250428816	486.015500057546
2004	null	null	null	19.0677361853832	488.114786450446
2003	null	null	null	18.9443911792905	493.684013045447
2002	null	null	null	19.087358684481	488.743285382219
2001	null	null	null	19.2461368653422	484.083871743709
2000	null	null	null	19.2954545454545	482.456799430981
1999	null	null	null	19.3656804733728	482.362414669942
1998	null	null	null	19.4289245982695	481.056745493943
1997	null	null	null	19.4291338582677	482.244866706037
1996	null	null	null	19.5847347994825	479.560836009444
1995	null	null	null	18.7973112719752	502.192459531232
1994	null	null	null	19.0122199592668	494.883790328922
1993	null	null	null	19.1043000914913	494.837783902195
1992	null	null	null	18.8626226583408	502.228115497502
1991	null	null	null	18.8259717314488	504.270073251502
1990	null	null	null	19.0009276437848	499.800704041559
1989	null	null	null	19.1257588898526	499.143176756376
1988	null	null	null	19.3283185840708	493.083160108052
1987	null	null	null	19.2285485164395	499.584206543624
1986	null	null	null	19.5504132231405	490.45326128694
1985	null	null	null	19.8083480305703	487.146809266722
1984	null	null	null	19.8818737270876	489.237133709112