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John Decker — 1940 US Census Record
Linked across censuses1940 United States Federal Census · Decatur-County, Iowa
Our Model Tree links this John Decker across the 1930 and 1940 US Censuses in Decatur-County, Iowa (XGBoost, ~Confirmed) — first a son (b.~1929), then head of a 7-person household.
Age 11
b. ~1929
Male
Son
Born: Iowa
Single
1940 Census Record Details
| Census Year | 1940 |
| Location | Decatur-County, Iowa |
| Surname | Decker |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Center Township |
| 1935 Residence (County) | Decatur County |
| Additional Details | |
| Highest Grade | No 5 |
| 1935 Residence | Same place |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
| Township / Ward | Center Township |
| Est. Birth Year | ~1929 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
7 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to John | Age | Birth yr |
|---|---|---|---|---|
| Hazel Decker | Daughter | — | 6 | ~1934 |
| Evelyn Decker | Daughter | — | 9 | ~1931 |
| Ardith Decker | Son | — | 15 | ~1925 |
| Walter Decker | Head | — | 41 | ~1899 |
| John Decker | Son | — | 11 | ~1929 |
| Gerald Decker | Son | — | 2 | ~1938 |
| Opal Decker | Spouse | — | 29 | ~1911 |
Census Appearances
1930
Clarke, Iowa
Son, age 1
Clarke, Iowa · implied b. ~1929 — 4 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Decker |
| Given Name | John W. |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 1 |
| Marital Status | Single |
| Birthplace | Iowa |
| Father's Birthplace | Missouri |
| Mother's Birthplace | Iowa |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
1940
Decatur-County, Iowa
Son, age 11
Decatur-County, Iowa · implied b. ~1929 — 7 household members
| Surname | Decker |
| Given Name | John |
| Relationship to Head | Son |
| Sex | M |
| Color / Race | White |
| Age | 11 |
| Marital Status | Single |
| Birthplace | Iowa |
| 1935 Residence (City) | Center Township |
| 1935 Residence (County) | Decatur County |
| Highest Grade | No 5 |
| 1935 Residence | Same place |
| Birth State | Iowa |
| Birth Country | United States |
| Birthplace (normalized) | iowa |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links John Decker across 2 US Census years (1930 and 1940) in 2 locations, using XGBoost record linkage.
Show:
This person
Anchor record
John Decker
Son · 1940 · age 11 · b. ~1929 · Iowa
★ You are viewing this record
Sibling
Gerald Decker
Sibling · 1940 · age 2
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Hazel Decker
Sibling · 1940 · age 6
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Ardith Decker
Sibling · 1940 · age 15
Source co-child of head (derived)
● Co-child · derived · ~0.88
Sibling
Evelyn Decker
Sibling · 1940 · age 9
Source co-child of head (derived)
● Co-child · derived · ~0.88
Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — Decatur-County, Iowa
Open full size
1940 US Federal Census — Decatur-County, Iowa
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-01154-00398)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | Carl Rex | 29 | Head | Farmer | Iowa |
| 42 | Lauretta Rex | 33 | Wife | Farmer | Missouri |
| 43 | Letty Ann Rex | 6 | Daughter | — | Iowa |
| 44 | Cecil Lee Rex | 2 | Daughter | — | Iowa |
| 45 | Lucille E Clarke | 35 | Head | — | Iowa |
| 46 | Ora Elma Kittinger | 73 | Head | Farmer | Iowa |
| 47 | Alice Kittinger | 47 | Daughter | Practical Nurse | Nebraska |
| 48 | Floyd Kittinger | 42 | Son | Farmer | Nebraska |
| 49 | Pearl Kittinger | 34 | Daughter | Teacher | Iowa |
| 50 | Marjorie Kittinger | 31 | Daughter | Teacher | Iowa |
| 51 | Floyd Smilla | 31 | Head | Common Laborer | Iowa |
| 52 | Pearl Smilla | 29 | Wife | — | Iowa |
| 53 | Elvin Smilla | 10 | Son | — | Iowa |
| 54 | Alvis Smilla | 8 | Daughter | — | Iowa |
| 55 | Carol Joyce Smilla | 2 | Daughter | — | Iowa |
| 56 | Claude Buck | 55 | Head | Painter | Iowa |
| 57 | Mary Buck | 60 | Wife | — | Iowa |
| 58 | Mary Cochran | 89 | Mother | — | Ohio |
| 59 | William A Rumley | 47 | Head | Farmer | Iowa |
| 60 | Etta Rumley | 45 | Wife | — | Iowa |
| 61 | Austin Rumley | 22 | Son | Farmer | Iowa |
| 62 | Ruby Rumley | 19 | Daughter | — | Iowa |
| 63 | Hazel Mae Rumley | 17 | Daughter | — | Iowa |
| 64 | Lester Dean Rumley | 10 | Son | — | Iowa |
| 65 | Elmer Tolley | 58 | Head | Farmer | Illinois |
| 66 | Elizabeth Tolley | 56 | Wife | — | Iowa |
| 67 | Walter Decker | 41 | Head | Common Laborer | Missouri |
| 68 | Opal Decker | 29 | Wife | — | Iowa |
| 69 | Ardith Decker | 15 | Son | — | Iowa |
| 70 | John Decker THIS PERSON | 11 | Son | — | Iowa |
| 71 | Evelyn Decker | 9 | Daughter | — | Iowa |
| 72 | Hazel Irene Decker | 6 | Daughter | — | Iowa |
| 73 | Gerald Decker | 2 | Son | — | Iowa |
| 74 | Gustave Brunotte | 51 | Head | Farmer | New York |
| 75 | Bessie Brunotte | 45 | Wife | — | Iowa |
| 76 | Clarence B Rumley | 31 | Head | Common Laborer | Iowa |
| 77 | Nina Rumley | 20 | Wife | — | Iowa |
| 78 | Dorothy Rumley | 8 | Daughter | — | Iowa |
| 79 | Junior Lee Rumley | 5 | Son | — | Iowa |
| 80 | Walter Buckingham | 36 | Head | Farmer | Iowa |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)