Solar Installer Three-Month Rolling Averages (2021)

PandasHardSenior level~10 min

Problem

Same three DataFrames as the other solar-installer problems: `installers`, `requests` (`request_id`, `household_id`, `requested_on`), and `bookings` (`request_id`, `installer_id`, `panel_count`, `job_minutes`).\n\nFirst total, per 2021 month, the `panel_count` and `job_minutes` of all bookings whose request was made that month (a month with no bookings totals 0). Then restrict to **months 1 through 10** and, within that range, compute a forward three-month rolling average over the current month and the next two: `avg_panel_count` and `avg_job_minutes`, each rounded to **two decimals**. The window never reaches past month 10, so months 9 and 10 average only the months that remain inside 1-10.\n\nReturn columns `month` (1-10), `avg_panel_count`, `avg_job_minutes`. Rows may be in any order.

Input data

Example rows — the live problem includes the full dataset.

installers

installer_id	onboarded_on
10	2020-12-10
8	2021-01-13
5	2021-02-16
7	2021-03-08
4	2021-05-17

requests

request_id	household_id	requested_on
6	75	2020-12-09
1	54	2021-02-09
10	63	2021-03-04
19	39	2021-04-06
3	41	2021-06-03

bookings

request_id	installer_id	panel_count	job_minutes
10	10	63	38
13	10	73	96
7	8	100	28
17	7	119	68
20	1	121	92

Expected output

Your answer should return 10 rows with the columns month, avg_panel_count, avg_job_minutes.

Starter code (Pandas (Python))

import pandas as pd

def solar_rolling_avg(installers, requests, bookings) -> pd.DataFrame:
    # Your code here
    return installers

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