import pandas as pd
import matplotlib.pyplot as plt
# Load data
df = pd.read_csv("data/processed/kwb_housing.csv")
# Filter to gemeente level and G4 cities
g4_codes = {"GM0363": "Amsterdam", "GM0599": "Rotterdam",
"GM0518": "Den Haag", "GM0344": "Utrecht"}
g4 = df[(df["region_type"] == "gemeente") & (df["region"].isin(g4_codes.keys()))].copy()
g4["city"] = g4["region"].map(g4_codes)
# Pivot for plotting
fig, axes = plt.subplots(1, 3, figsize=(12, 4))
variables = [
("woningvoorraad", "Total Housing Stock"),
("koopwoningen", "Owner-occupied (%)"),
("huurwoningen", "Rental (%)"),
]
colors = {"Amsterdam": "#1b9e77", "Rotterdam": "#d95f02",
"Den Haag": "#7570b3", "Utrecht": "#e7298a"}
for ax, (var, title) in zip(axes, variables):
for city in g4_codes.values():
city_data = g4[g4["city"] == city].sort_values("year")
ax.plot(city_data["year"], city_data[var],
label=city, color=colors[city], linewidth=1.5)
ax.set_title(title)
ax.set_xlabel("Year")
ax.spines[["top", "right"]].set_visible(False)
axes[0].set_ylabel("Number of dwellings")
axes[1].set_ylabel("Percentage")
axes[2].set_ylabel("Percentage")
axes[2].legend(loc="upper right", frameon=False)
plt.tight_layout()
plt.show()
