Back to guides

Guide

Trend and Time Series Analysis in Excel Using AI

Analyze trends, detect seasonality, and forecast demand from Excel data without pivot tables, formulas, or separate forecasting tools.

Introduction

Most clinics do not struggle with collecting data. They struggle with understanding it in time.

Patient demand spikes unexpectedly. Medications run low. Staffing falls behind.

Not because the data is missing, but because the trends are not visible early enough.

Trend and time series analysis helps uncover how key metrics evolve over time, so decisions can be made before problems occur.

Traditional Excel workflow

To analyze trends in Excel, analysts typically:

  • group data by time, such as month, week, or day
  • build pivot tables for aggregation
  • create charts manually
  • interpret patterns by inspection
  • use separate tools for forecasting

This process takes hours, requires multiple tools, and breaks easily as the data grows.

With Decide

Decide turns the workflow into a single instruction.

You describe the trends, comparisons, patterns, and forecasts you want. Decide executes the analysis, creates charts, explains what changed, and produces projections you can use for planning.

Scenario

You are a data analyst supporting a hypertension clinic in Nigeria.

The clinic has monthly data in Excel, including:

  • number of patient visits
  • new patients
  • follow-up visits
  • medication dispensed by drug type

The data is clean, but no insights have been extracted.

Business objective

The clinic wants to:

  • understand how patient demand is changing
  • identify which medications will be needed more
  • detect peak periods in advance
  • improve procurement and staffing decisions

Prompt

Analyze this dataset and provide the following:

1. Show the trend of Number_of_Visits over time.
2. Compare trends between New_Patients and Follow_Up_Visits.
3. Analyze Total_Medication_Dispensed over time.
4. Show medication trends by Drug_Type.
5. Identify peak months with the highest patient visits.
6. Highlight any noticeable patterns or seasonality.
7. Forecast patient visits for the next 3 months.
8. Provide insights that can support decision-making in the clinic.
9. Present the results clearly with explanations.

What Decide produces instantly

Decide can generate:

  • a time-series chart showing patient visit growth over time
  • a clear comparison of new versus returning patients
  • medication demand trends broken down by drug type
  • identification of peak months and seasonal spikes
  • detection of recurring patterns in patient flow
  • a 3-month forecast of patient visits
  • estimated future medication demand
  • written insights for decision-making

What this enables

Instead of only analyzing data in Excel, the clinic can answer:

  • When will patient demand spike next?
  • Which drugs are likely to run out soon?
  • Are we seeing more new patients or repeat visits?
  • How should staffing change next quarter?

Example outputs

What the analysis looks like

These are the charts Decide generated from the clinic dataset. Each one maps to a decision the clinic needs to make: demand, staffing, medication planning, forecasting, and quality review.

Demand trend

Start with patient demand

Decide first turns monthly visits into a readable trend, making it clear where demand is stable, where it peaks, and where the clinic should watch for dips.

Line chart showing monthly patient visits from January 2025 to June 2026
Patient visits averaged about 187 per month, with a high of 206 visits and a low of 160 visits.

Patient mix

Compare new patients with follow-up visits

The next view separates acquisition from continuity of care, so the clinic can see whether growth is coming from new patients or returning patients.

Chart comparing new patients and follow-up visits by month
Follow-up visits made up roughly two-thirds of the activity, showing a strong continuity-of-care base.

Medication demand

Connect patient demand to medication planning

Decide then connects visits to medication volume, both in aggregate and by drug type, so procurement decisions are tied to the actual operating pattern.

Line chart showing total medication dispensed over time
Total medication dispensed averaged about 514 units per month, with demand moving broadly alongside visit volume.
Line chart showing medication trends by drug type
Drug-level trends make it easier to plan inventory for Amlodipine, Lisinopril, and Hydrochlorothiazide separately.
Pie chart showing medication distribution by drug type
The medication mix shows Amlodipine at 42%, Lisinopril at 33%, and Hydrochlorothiazide at 25% of dispensed units.

Planning signal

Identify peak months and forecast what comes next

The forecast view turns the historical trend into a planning input. Instead of reacting after demand moves, the clinic can prepare staffing and inventory in advance.

Bar chart showing the highest patient visit and medication months
Peak analysis highlights the busiest periods, including June 2025, September 2025, and February 2026.
Forecast chart showing projected patient visits for the next three months
The 3-month forecast projects visits stabilizing around 188 to 189 per month.

Operating quality

Review movement and efficiency

Finally, Decide adds operational checks that help validate the output before a team acts on it.

Chart showing month-over-month changes in visits and medication dispensed
Month-over-month changes show where visits and medication demand grew or declined together.
Chart showing medication units dispensed per patient visit
Medication per visit stayed near 2.75 units, which helps the clinic estimate inventory needs from expected visit volume.

Output review

After running the analysis, verify that:

  • trends are smooth and realistic, with no unexplained spikes
  • new patient and follow-up trends align with total visits
  • drug trends reflect expected variation
  • peak months are correctly identified
  • forecast values are reasonable and not extreme

Forecasts should support planning, not replace judgment. If the source data has gaps, sudden one-off events, or inconsistent date formatting, those issues should be reviewed before acting on the forecast.

Why use Decide

Decide is useful for this workflow because it:

  • removes the need for pivot tables, formulas, and manual charting
  • automatically detects patterns that may be easy to miss
  • combines analysis, visualization, and explanation in one run
  • generates forecasts without requiring you to build models manually
  • turns raw Excel data into decisions faster

End goal

The goal is to turn historical Excel data into:

  • clear trends
  • predictable patterns
  • actionable forecasts

That way, decisions are made ahead of demand, not after problems occur.

Closing

Instead of spending hours building charts and models in Excel, you ask once and get the analysis, forecast, and decision support in seconds.

Get started today with Decide