import urllib.request
from pathlib import Path

import altair as alt
import pandas as pd

url = "https://fiscaldata.treasury.gov/static-data/HstDebt_all_years.csv.zip"
local_file = Path(Path(url).name)
if not local_file.exists():
    with urllib.request.urlopen(url) as req:
        resp = req.read()
    local_file.write_bytes(resp)

df = pd.read_csv(local_file, parse_dates=["Record Date"])

df.head(5)
Record Date Debt Outstanding Amount Source Line Number Fiscal Year Fiscal Quarter Number Calendar Year Calendar Quarter Number Calendar Month Number Calendar Day Number
0 1790-01-01 71060508.50 1 1790 2 1790 1 1 1
1 1791-01-01 75463476.52 1 1791 2 1791 1 1 1
2 1792-01-01 77227924.66 1 1792 2 1792 1 1 1
3 1793-01-01 80358634.04 1 1793 2 1793 1 1 1
4 1794-01-01 78427404.77 1 1794 2 1794 1 1 1 
alt.Chart(df).mark_line().encode(
    x=alt.X("Fiscal Year", axis = alt.Axis(format=("d"))),
    y="Debt Outstanding Amount",
)