Why Waterfall charts in Excel? - Purpose & Use Cases

The Big Idea

See how each number moves your total up or down with one simple chart!

The Scenario

Imagine you have a list of monthly expenses and incomes, and you want to show how each one adds up to your final bank balance. You try to draw this by hand or use simple bar charts, but it's hard to see how each step changes the total.

The Problem

Manually calculating and drawing each step is slow and confusing. You might make mistakes adding or subtracting values, and the chart won't clearly show the flow of money. It's frustrating to explain the story behind the numbers.

The Solution

Waterfall charts automatically show how each value increases or decreases the total step-by-step. They make it easy to see the flow from start to finish, highlighting gains and losses clearly without extra work.

Before vs After

✗ Before

Create separate bar charts for each value and try to explain changes verbally

✓ After

Insert a Waterfall chart and let Excel show the stepwise changes visually

What It Enables

Waterfall charts let you quickly and clearly tell the story of how numbers build up or break down over time or categories.

Real Life Example

A business owner uses a waterfall chart to show how monthly sales, expenses, and taxes affect the final profit, making it easy for the team to understand financial health.

Key Takeaways

Manual tracking of step changes is slow and error-prone.

Waterfall charts visualize increases and decreases clearly.

They help explain complex number flows simply and quickly.

Practice

1. What is the main purpose of a Waterfall chart in Excel?

easy

A. To show how an initial value changes step-by-step to a final value

B. To display data in a pie format

C. To compare values across categories side-by-side

D. To create a 3D visual effect for data

Solution

1. Step 1: Understand Waterfall chart purpose

   Waterfall charts visualize how an initial value changes through a series of positive and negative values to reach a final total.

2. Step 2: Compare with other chart types

   Pie charts show parts of a whole, bar charts compare categories, and 3D effects are visual styles, not purposes.

3. Final Answer:

   To show how an initial value changes step-by-step to a final value -> Option A

4. Quick Check:

   Waterfall charts = step-by-step changes [OK]

Hint: Waterfall = track increases and decreases stepwise [OK]

Common Mistakes:

• Confusing waterfall with pie or bar charts
• Thinking waterfall shows only totals, not changes
• Assuming waterfall charts use formulas directly

2. Which of these is the correct way to prepare data for a Waterfall chart in Excel?

easy

A. Use only positive values for all changes

B. Enter formulas directly into the chart

C. Use text labels only without numbers

D. Include both positive and negative values to show increases and decreases

Solution

1. Step 1: Identify data requirements for Waterfall charts

   Waterfall charts need positive values for increases and negative values for decreases to show step changes clearly.

2. Step 2: Eliminate incorrect options

   Using only positive values hides decreases, text labels alone don't create the chart, and formulas are not entered directly into charts.

3. Final Answer:

   Include both positive and negative values to show increases and decreases -> Option D

4. Quick Check:

   Positive and negative values = correct data setup [OK]

Hint: Use positive & negative numbers for changes [OK]

Common Mistakes:

• Using only positive numbers hides decreases
• Trying to put formulas inside the chart
• Using text without numbers for values

3. Given this data for a Waterfall chart:
Start: 100
Increase: 30
Decrease: -20
Increase: 10
What is the final total shown in the chart?

medium

A. 130

B. 120

C. 140

D. 150

Solution

1. Step 1: Add increases and decreases to start value

   Start with 100, add 30 (increase) = 130, subtract 20 (decrease) = 110, add 10 (increase) = 120.

2. Step 2: Calculate final total

   Final total after all changes is 120.

3. Final Answer:

   120 -> Option B

4. Quick Check:

   100 + 30 - 20 + 10 = 120 [OK]

Hint: Add positive and subtract negative values stepwise [OK]

Common Mistakes:

• Adding negative values instead of subtracting
• Ignoring decreases in calculation
• Mixing up order of operations

4. You created a Waterfall chart but it shows all bars starting from zero instead of connecting. What is the likely cause?

medium

A. Data does not include negative values

B. The data range is not formatted as a table

C. The 'Set as total' option is missing for subtotal rows

D. Chart type selected is not Waterfall

Solution

1. Step 1: Understand Waterfall chart bar connections

   Bars connect when Excel knows which rows are totals or subtotals, set by 'Set as total' option.

2. Step 2: Identify missing 'Set as total' setting

   If subtotal rows are not marked as totals, bars start from zero instead of continuing from previous values.

3. Final Answer:

   The 'Set as total' option is missing for subtotal rows -> Option C

4. Quick Check:

   Missing 'Set as total' = disconnected bars [OK]

Hint: Mark subtotal rows as totals to connect bars [OK]

Common Mistakes:

• Assuming negative values fix bar connections
• Thinking table format affects bar start points
• Choosing wrong chart type without checking data

5. You want to create a Waterfall chart showing monthly sales changes, but some months have zero change. How should you handle zero values to keep the chart clear?

hard

A. Leave zero values as is; Excel will show no bar for those months

B. Remove rows with zero values from the data

C. Replace zero values with small positive numbers

D. Convert zero values to negative numbers

Solution

1. Step 1: Understand zero values in Waterfall charts

   Zero values represent no change, so Excel shows no bar for those points, keeping the chart accurate and clear.

2. Step 2: Avoid altering zero values

   Replacing zeros with small positives or negatives misrepresents data; removing rows loses timeline context.

3. Final Answer:

   Leave zero values as is; Excel will show no bar for those months -> Option A

4. Quick Check:

   Zero values = no bar, keep data accurate [OK]

Hint: Keep zeros; chart shows no bar for no change [OK]

Common Mistakes:

• Changing zeros to small numbers distorts data
• Deleting zero rows breaks timeline
• Using negative numbers for zero changes