Why a text and a chart travel together
Words explain and argue. Charts show many numbers at once. A writer uses both: the chart gives the evidence and the sentence tells you what to notice. If you read only the words, you trust the writer. If you read both, you can check the writer.
Step 1: Read the chart first
- Title: what is it about?
- What is measured and its unit (%, kg, rupees, people).
- Axes: which labels are on the bottom (here: years) and the side (values).
- Where the axis starts: 0 or a higher number?
- Source and date: who made the data, and when?
Step 2: Find each sentence in the chart
Take one sentence at a time. Underline its numbers or words like rose, fell, doubled, most, half. Find the matching bars, points or slices. Write the two numbers. Example: "rose from 20% to 40%" means the later number is two times the earlier one.
Step 3: Check the words against the numbers
Do the arithmetic yourself. Change = new − old. Percent change = change ÷ old × 100. Times = new ÷ old. 15 → 40: change 25, percent change about 167%, times about 2.7. So "tripled" is too strong; "almost tripled" is fair. Also watch the difference between percent points and percent: from 20% to 40% is +20 percentage points but +100% in relative terms.
Step 4: Interpret the writer's aim
Every writer chooses: which data to show, which chart type, which words, and which part to highlight. Ask: Who is the writer? What do they want me to think or do? What have they left out? A cut axis (starting at 30 instead of 0) makes small changes look big. Picking only two years can hide ups and downs in between. Strong words like "shot up" add feeling that numbers alone do not carry.
Try it
Open a newspaper or website chart with its article. Write down (1) the unit, (2) where the axis starts, (3) one sentence and its two numbers, (4) whether the words match. Then in the 3D, move the slider and see how the picture changes while the numbers stay the same.
Key formulas and definitions
- Change = new − old
- Percent change = (new − old) ÷ old × 100
- Times = new ÷ old
- Percentage points = new % − old %
- Honest bars start at 0
Worked examples
1. A chart shows cycling: 20% in 2021 and 40% in 2023. The text says "doubled". Is it right?
Times = 40 ÷ 20 = 2. Yes, doubled. In percentage points it is +20; in percent change it is +100%.
2. The chart shows 15% in 2020 and 40% in 2023. The text says "tripled". Is it right?
Times = 40 ÷ 15 = 2.67. That is less than 3, so "tripled" is too strong. A fair phrase is "almost tripled".
3. A bar chart axis starts at 70%. Bars show 72% and 76%. The first bar is 2 units tall and the second 6 units. What does the eye think, and what is true?
The eye thinks the second bar is 3 times the first. The truth: 76 ÷ 72 = 1.06, a rise of about 6%. The cut axis exaggerates.
Common mistakes
- Reading only the sentence and trusting it without looking at the chart.
- Not checking where the axis starts.
- Mixing up percentage points and percent change.
- Thinking a chart is neutral. Someone chose what it shows.