Completed fertility in Japan

This page gives information of type completed fertility about the country Japan.
See all pages giving information on completed fertility for particular countries|See all pages giving information about Japan

Data sources

Some data on this page comes from the Human Fertility Database (website www.humanfertility.org) (data downloaded December 2, 2013, last updated by HFD August 8, 2012). The data collected by the Human Fertility Database is based on government data collection by the government of Japan. You can download the data yourself here. Details about the modalities of data collection are available here. Where available, we use HFD data because of its higher reliability.

Trends in completed fertility

Range of birth cohorts	Trend in fertility	Some numbers	Details
1932-1944	stayed roughly steady, declining and then bouncing back	CCF decreased from 2.06 to 2.035 CCF40 decreased from 2.047 to 2.027	The fertility seems to have gone up a bit for the cohorts born during World War II, but the overall variation is too little. Mean CCF for the period is 2.036 and standard deviation is 0.023.
1945-1959	stayed roughly steady, but lower than the 1932-1944 level	CCF increased from 1.851 to 1.87 CCF40 increased from 1.842 to 1.85	Mean CCF was 1.95 and standard deviation 0.049. Mean CCF40 was 1.94 and standard deviation 0.049.
1959-1969	rapid decline	CCF data unavailable CCF40 decreased from 1.85 to 1.444	Slope for rate of decline using linear regression estimate is -0.04.

CCF and CC40, not broken down by birth order

Cohort	CCF	CCF minus previous year's CCF	CCF40	CCF40 minus previous year's CCF40
1932	2.06		2.047
1933	2.035	-0.025	2.024	-0.023
1934	2.008	-0.027	1.998	-0.026
1935	2.045	0.037	2.035	0.037
1936	2.035	-0.01	2.026	-0.009
1937	2.051	0.016	2.042	0.016
1938	2.009	-0.042	2.001	-0.041
1939	1.985	-0.024	1.976	-0.025
1940	2.052	0.067	2.043	0.067
1941	2.071	0.019	2.062	0.019
1942	2.031	-0.04	2.022	-0.04
1943	2.053	0.022	2.044	0.022
1944	2.036	-0.017	2.027	-0.017
1945	1.851	-0.185	1.842	-0.185
1946	1.905	0.054	1.896	0.054
1947	2.021	0.116	2.01	0.114
1948	1.987	-0.034	1.976	-0.034
1949	1.992	0.005	1.98	0.004
1950	1.969	-0.023	1.956	-0.024
1951	1.962	-0.007	1.949	-0.007
1952	1.982	0.02	1.968	0.019
1953	1.987	0.005	1.973	0.005
1954	1.983	-0.004	1.968	-0.005
1955	1.977	-0.006	1.961	-0.007
1956	1.946	-0.031	1.929	-0.032
1957	1.918	-0.028	1.9	-0.029
1958	1.909	-0.009	1.89	-0.01
1959	1.87	-0.039	1.85	-0.04
1960	unavailable		1.805	-0.045
1961	unavailable		1.762	-0.043
1962	unavailable		1.719	-0.043
1963	unavailable		1.672	-0.047
1964	unavailable		1.66	-0.012
1965	unavailable		1.595	-0.065
1966	unavailable		1.493	-0.102
1967	unavailable		1.506	0.013
1968	unavailable		1.497	-0.009
1969	unavailable		1.444	-0.053
Mean (1932-1959)	1.9903571429	-0.007037037	1.9783928571	-0.0072962963
Median (1932-1959)	1.9895	-0.009	1.978	-0.009
Standard deviation (1932-1959)	0.0582747098	0.0509467909	0.0602871765	0.0507488649
Slope for best linear fit (using linear regression) (1932-1959)	-0.004805145	-0.0004334554	-0.0051409414	-0.000510989
$R^{2}$ -- goodness of linear fit (square of the correlation) as a function of time	0.4600738487	0.0045603249	0.4920510998	0.0063872072
Multiplier for best logarithmic fit (using log-linear regression) (1932-1959)	0.997579501		0.9973921665
Mean (1960-1969)			1.6153	-0.0406
Median (1960-1969)			1.6275	-0.044
Standard deviation (1960-1969)			0.1265473561	0.0321116109
Slope for best linear fit (using linear regression) (1960-1969)			-0.0410363636	0.0013818182
$R^{2}$ -- goodness of linear fit (square of the correlation) as a function of time			0.9639245164	0.01697419
Multiplier for best logarithmic fit (using log-linear regression) (1960-1969)			0.9749241926

Completed cohort fertilities, by birth order where available

Cohort	CCF	CCF1	CCF2	CCF3	CCF4	CCF5+	CCF1 proportion	CCF2 proportion	CCF3 proportion	CCF4 proportion	CCF5+ proportion
1932	2.06
1933	2.035
1934	2.008
1935	2.045
1936	2.035
1937	2.051
1938	2.009
1939	1.985
1940	2.052
1941	2.071
1942	2.031
1943	2.053
1944	2.036
1945	1.851
1946	1.905
1947	2.021
1948	1.987
1949	1.992
1950	1.969
1951	1.962
1952	1.982
1953	1.987	0.887	0.769	0.282	0.04	0.01	0.4464016105	0.3870156014	0.1419224962	0.0201308505	0.0050327126
1954	1.983	0.882	0.765	0.286	0.041	0.01	0.4447806354	0.3857791225	0.1442259203	0.0206757438	0.0050428643
1955	1.977	0.879	0.761	0.286	0.042	0.009	0.4446130501	0.3849266566	0.1446636318	0.0212443096	0.004552352
1956	1.946	0.867	0.746	0.283	0.041	0.009	0.4455292909	0.3833504625	0.1454265159	0.0210688592	0.0046248715
1957	1.918	0.858	0.733	0.277	0.041	0.009	0.4473409802	0.382168926	0.1444212722	0.0213764338	0.0046923879
1958	1.909	0.858	0.727	0.274	0.04	0.009	0.4494499738	0.3808276585	0.1435306443	0.0209533787	0.0047145102
1959	1.87	0.846	0.71	0.265	0.039	0.009	0.4524064171	0.3796791444	0.1417112299	0.020855615	0.0048128342
Mean (1953-1959)	1.9414285714	0.8681428571	0.7444285714	0.279	0.0405714286	0.0092857143	0.4472174226	0.3833925103	0.1437002444	0.0209007415	0.0047817904
Median (1953-1959)	1.946	0.867	0.746	0.282	0.041	0.009	0.4464016105	0.3833504625	0.1442259203	0.0209533787	0.0047145102
Standard deviation (1953-1959)	0.0443353025	0.0150712593	0.022074549	0.0076157731	0.0009759001	0.00048795	0.0028331738	0.0026783947	0.0014053277	0.0004124619	0.0001922976
Slope for best linear fit (using linear regression) (1953-1959)	-0.0199285714	-0.0068571429	-0.0100357143	-0.003	-0.0002142857	-0.0001785714	0.0010743224	-0.0012382154	-8.09539448686275E-005	0.0001022031	-0.000042011
Multiplier for best logarithmic fit (using log-linear regression) (1953-1959)	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583	0.9897520583

Completed cohort fertilities till age 40, where available

Cohort	CCF40	CCF40_1	CCF40_2	CCF40_3	CCF40_4	CCF40_5+	CCF40_1 proportion	CCF40_2 proportion	CCF40_3 proportion	CCF40_4 proportion	CCF40_5+ proportion
1932	2.047
1933	2.024
1934	1.998
1935	2.035
1936	2.026
1937	2.042
1938	2.001
1939	1.976
1940	2.043
1941	2.062
1942	2.022
1943	2.044
1944	2.027
1945	1.842
1946	1.896
1947	2.01
1948	1.976
1949	1.98
1950	1.956
1951	1.949
1952	1.968
1953	1.973	0.883	0.765	0.278	0.039	0.009	0.4475418145	0.3877344146	0.1409021794	0.0197668525	0.0045615813
1954	1.968	0.878	0.76	0.282	0.039	0.008	0.4461382114	0.3861788618	0.1432926829	0.0198170732	0.0040650407
1955	1.961	0.875	0.756	0.283	0.039	0.008	0.4462009179	0.3855175931	0.1443141254	0.0198878123	0.0040795512
1956	1.929	0.863	0.741	0.279	0.039	0.008	0.4473820632	0.3841368585	0.1446345257	0.0202177294	0.0041472265
1957	1.9	0.853	0.728	0.273	0.038	0.008	0.4489473684	0.3831578947	0.1436842105	0.02	0.0042105263
1958	1.89	0.853	0.722	0.269	0.038	0.008	0.4513227513	0.382010582	0.1423280423	0.0201058201	0.0042328042
1959	1.85	0.84	0.704	0.261	0.037	0.008	0.4540540541	0.3805405405	0.1410810811	0.02	0.0043243243
1960	1.805	0.826	0.686	0.249	0.036	0.008	0.4576177285	0.3800554017	0.1379501385	0.0199445983	0.004432133
1961	1.762	0.815	0.668	0.237	0.035	0.007	0.4625425653	0.3791146425	0.1345062429	0.0198637911	0.0039727582
1962	1.719	0.804	0.65	0.225	0.033	0.007	0.4677137871	0.3781268179	0.1308900524	0.0191972077	0.004072135
1963	1.672	0.789	0.631	0.214	0.031	0.007	0.4718899522	0.3773923445	0.1279904306	0.0185406699	0.0041866029
1964	1.66	0.792	0.625	0.206	0.031	0.007	0.4771084337	0.3765060241	0.1240963855	0.0186746988	0.0042168675
1965	1.595	0.768	0.598	0.193	0.029	0.007	0.4815047022	0.3749216301	0.1210031348	0.0181818182	0.0043887147
1966	1.493	0.726	0.557	0.176	0.027	0.007	0.4862692565	0.373074347	0.1178834561	0.0180843938	0.0046885466
1967	1.506	0.739	0.56	0.173	0.027	0.007	0.4907038513	0.3718459495	0.114873838	0.0179282869	0.0046480744
1968	1.497	0.741	0.556	0.168	0.026	0.007	0.49498998	0.3714094856	0.1122244489	0.0173680695	0.0046760187
1969	1.444	0.719	0.534	0.159	0.025	0.007	0.4979224377	0.3698060942	0.1101108033	0.0173130194	0.0048476454
Mean (1953-1969)	1.7425882353	0.8096470588	0.6612352941	0.2308823529	0.0334705882	0.0075294118	0.4664617574	0.378913499	0.1312803399	0.0191112848	0.0043382677
Median (1953-1969)	1.762	0.815	0.668	0.237	0.035	0.007	0.4625425653	0.3791146425	0.1345062429	0.0197668525	0.0042328042
Standard deviation (1953-1969)	0.1854976613	0.0556596141	0.0795420717	0.0448760548	0.0051734617	0.0006242643	0.0185124	0.0054832404	0.0123492838	0.0010215973	0.00026236
Slope for best linear fit (using linear regression) (1953-1969)	-0.036252451	-0.0108308824	-0.0156004902	-0.0087058824	-0.000997549	-0.0001078431	0.0035779784	-0.0010829371	-0.0023354568	-0.0001824256	3.11583339680162E-005
Multiplier for best logarithmic fit (using log-linear regression) (1953-1969)	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327	0.9791004327
R^2 for linear regression (1953-1969)	0.9739531157	0.9655782504	0.9808957967	0.9597020647	0.9480826465	0.7610062893	0.9525551905	0.9946540434	0.9120115036	0.8131160552	0.359661059

Parity progression ratios

Note that the parity progression ratio (PPR) data is strictly deducible from the completed cohort fertility data (broken down by birth order) above, but it is included for completeness' sake.

Cohort	PPR from 0 to 1	PPR from 1 to 2	PPR from 2 to 3	PPR from 3 to 4
1953	0.887	0.867	0.367	0.144
1954	0.882	0.868	0.374	0.144
1955	0.879	0.865	0.377	0.145
1956	0.867	0.86	0.379	0.146
1957	0.858	0.855	0.378	0.147
1958	0.858	0.848	0.376	0.147
1959	0.846	0.84	0.373	0.149
Maximum	0.887	0.868	0.379	0.149
Minimum	0.846	0.84	0.367	0.144
Average (arithmetic mean)	0.8681428571	0.8575714286	0.3748571429	0.146
Geometric mean	0.8680305627	0.8575157207	0.374838175	0.1459902411
Median	0.867	0.86	0.376	0.146
Standard deviation	0.0150712593	0.0105333936	0.0040590874	0.0018257419
Slope for best linear fit (using linear regression)	-0.0068571429	-0.0046785714	0.0008214286	0.0008214286
Multiplier for best logarithmic fit (using linear regression on logarithm)	0.9921263898	0.9945448817	1.0022155011	1.0056349756
$R^{2}$ for linear regression	0.9660377358	0.9206545064	0.1911127168	0.9446428571