diff --git a/changelog.d/backdate-blind-sga.added.md b/changelog.d/backdate-blind-sga.added.md
new file mode 100644
index 00000000000..8ef08eef54a
--- /dev/null
+++ b/changelog.d/backdate-blind-sga.added.md
@@ -0,0 +1 @@
+Backdate blind SGA parameter values to 1975.
diff --git a/changelog_entry.yaml b/changelog_entry.yaml
index e69de29bb2d..8b137891791 100644
--- a/changelog_entry.yaml
+++ b/changelog_entry.yaml
@@ -0,0 +1 @@
+
diff --git a/policyengine_us/parameters/gov/ssa/sga/blind.yaml b/policyengine_us/parameters/gov/ssa/sga/blind.yaml
index 58aeb893b39..98d13fd2fb8 100644
--- a/policyengine_us/parameters/gov/ssa/sga/blind.yaml
+++ b/policyengine_us/parameters/gov/ssa/sga/blind.yaml
@@ -1,7 +1,58 @@
 description: The Social Security Administration considers blind individuals earning more than this amount, net of impairment-related work expenses, to be engaging in Substantial Gainful Activity.
 
 values:
+  1975-01-01: 200
+  1976-01-01: 230
+  1977-01-01: 240
+  1978-01-01: 334
+  1979-01-01: 375
+  1980-01-01: 417
+  1981-01-01: 459
+  1982-01-01: 500
+  1983-01-01: 550
+  1984-01-01: 580
+  1985-01-01: 610
+  1986-01-01: 650
+  1987-01-01: 680
+  1988-01-01: 700
+  1989-01-01: 740
+  1990-01-01: 780
+  1991-01-01: 810
+  1992-01-01: 850
+  1993-01-01: 880
+  1994-01-01: 930
+  1995-01-01: 940
+  1996-01-01: 960
+  1997-01-01: 1_000
+  1998-01-01: 1_050
+  1999-01-01: 1_110
+  2000-01-01: 1_170
+  2001-01-01: 1_240
+  2002-01-01: 1_300
+  2003-01-01: 1_330
+  2004-01-01: 1_350
+  2005-01-01: 1_380
+  2006-01-01: 1_450
+  2007-01-01: 1_500
+  2008-01-01: 1_570
+  2009-01-01: 1_640
+  2010-01-01: 1_640
+  2011-01-01: 1_640
+  2012-01-01: 1_690
+  2013-01-01: 1_740
+  2014-01-01: 1_800
+  2015-01-01: 1_820
+  2016-01-01: 1_820
+  2017-01-01: 1_950
+  2018-01-01: 1_970
+  2019-01-01: 2_040
+  2020-01-01: 2_110
+  2021-01-01: 2_190
+  2022-01-01: 2_260
+  2023-01-01: 2_460
+  2024-01-01: 2_590
   2025-01-01: 2_700
+  2026-01-01: 2_830
 metadata:
   label: Blind Substantial Gainful Activity limit
   unit: currency-USD