# Population (1 January) — Kocaeli, Sakarya, Düzce, Bolu, Yalova (NUTS-2 TR42)

Population (1 January) — Kocaeli, Sakarya, Düzce, Bolu, Yalova (NUTS-2 TR42) was 4,287,376 persons in 2025, up 1.1% from 2024.
That is the highest reading since the series began in 2001.
Over the past ten years it has ranged from 3,522,353 persons (2015) to 4,287,376 persons (2025), averaging 3,940,742 persons.

- Source agency: Eurostat (Statistical Office of the European Union)
- Makrognosis code: `TR-42.POP.A.NSA`
- Frequency: annual
- Units: persons
- Coverage: 2001-01-01 to 2025-01-01 (25 observations)
- Page: https://makrognosis.robomacro.com/data/turkey/population-1-january-kocaeli-sakarya-duzce-bolu-yalova-nuts-2-tr42

## Recent data

| Period | Value |
|---|---:|
| 2025 | 4,287,376 persons |
| 2024 | 4,240,456 persons |
| 2023 | 4,181,440 persons |
| 2022 | 4,106,308 persons |
| 2021 | 4,026,438 persons |
| 2020 | 3,961,953 persons |
| 2019 | 3,878,979 persons |
| 2018 | 3,805,481 persons |
| 2017 | 3,719,652 persons |
| 2016 | 3,617,728 persons |
| 2015 | 3,522,353 persons |
| 2014 | 3,448,702 persons |
| 2013 | 3,376,330 persons |
| 2012 | 3,315,463 persons |
| 2011 | 3,246,147 persons |
| 2010 | 3,193,210 persons |
| 2009 | 3,136,555 persons |
| 2008 | 3,048,651 persons |
| 2007 | 2,991,414 persons |
| 2006 | 2,934,116 persons |
| 2005 | 2,878,130 persons |
| 2004 | 2,823,734 persons |
| 2003 | 2,771,438 persons |
| 2002 | 2,719,049 persons |

## API

```
curl -H "X-API-Key: $MAKROGNOSIS_KEY" \
  "https://makrognosis.robomacro.com/v1/series/TR-42.POP.A.NSA"

# Python
import requests
r = requests.get("https://makrognosis.robomacro.com/v1/series/TR-42.POP.A.NSA",
                 headers={"X-API-Key": KEY})
obs = r.json()["observations"]
```