Koga (古河市)

City

Ibaraki (茨城) — 2025 — Based on Basic Resident Register

Total Population

139,812

-687 (-0.49%)

Young (0–14)

10.6%

14,802

Working Age (15–64)

59.7%

83,525

Aging Rate

29.7%

41,482

Population Trends (1995–2025)

* Data before 2012 includes Japanese residents only (foreign residents were added to the Basic Resident Register in July 2012)

Category	Total	Male	Female
Total	139,812	70,892	68,920
Young (0–14)	14,802	7,519	7,283
Working Age (15–64)	83,525	44,598	38,927
Elderly (65+)	41,482	18,774	22,708

Year	Total Population	0–14	15–64	65+	Aging Rate
2025	139,812	14,802	83,525	41,482	29.7%
2024	140,499	15,370	83,808	41,318	29.4%
2023	140,959	15,837	84,072	41,047	29.1%
2022	141,371	16,205	84,393	40,770	28.8%
2021	142,260	16,607	85,313	40,337	28.4%
2020	142,992	16,965	86,335	39,689	27.8%
2019	143,693	17,363	87,253	39,074	27.2%
2018	144,480	17,690	88,454	38,336	26.5%
2017	144,406	17,893	88,987	37,523	26.0%
2016	144,715	18,081	90,202	36,429	25.2%
2015	145,214	18,381	91,569	35,261	24.3%
2014	145,815	18,531	93,262	34,019	23.3%
2013	146,066	18,707	94,193	33,166	22.7%
2012	144,114	18,801	93,700	31,613	21.9%
2011	144,536	19,047	94,927	30,562	21.1%
2010	145,092	19,334	95,632	30,126	20.8%
2009	145,493	19,613	96,664	29,216	20.1%
2008	145,895	19,910	97,851	28,134	19.3%
2007	145,996	20,315	98,555	27,126	18.6%
2006	146,547	20,670	99,921	25,956	17.7%
2005	58,979	7,978	39,195	11,806	20.0%
2004	59,244	8,163	39,625	11,456	19.3%
2003	59,309	8,335	39,805	11,169	18.8%
2002	59,501	8,566	40,157	10,778	18.1%
2001	59,455	8,680	40,438	10,337	17.4%
2000	59,439	8,843	40,725	9,871	16.6%
1999	59,427	8,955	40,968	9,504	16.0%
1998	59,118	9,082	40,924	9,112	15.4%
1997	59,144	9,242	41,158	8,744	14.8%
1996	59,109	9,401	41,337	8,371	14.2%
1995	59,132	9,617	41,523	7,992	13.5%