Data Interpretation: Tables
CSAT · Data Interpretation
Introduction
Data interpretation (tables) questions give you data and ask for quick, accurate calculations. They need no outside knowledge, so they are reliable marks once the reading and arithmetic are disciplined.
Key concepts
Reading a table
Note the title, units and base year before reading the numbers. Values may be in thousands, crore or percentages; a column total may be given or may have to be computed.
Core calculations
| Question type | Formula |
|---|---|
| Percentage change | (new − old)/old × 100 |
| Share of a total | part/total × 100 |
| Average | sum/number of items |
| Ratio | a : b, simplified |
| Growth over n years (CAGR, approx.) | use successive % changes |
Approximation
Options are usually far apart. Round 187 to 190 and 412 to 410: 190/410 ≈ 0.46. Use fractions: 33.3% = 1/3, 12.5% = 1/8.
Comparing growth
The largest absolute increase is not always the largest percentage increase – a small base can show a big percentage.
Workflow
Read all questions first, compute row/column totals you will need more than once, and keep a small table of intermediate results.
- % change = (new − old)/old × 100
- Share = part/total × 100
- Average = sum/count
- Pie angle = % × 3.6
Solved examples
Data set: Production table
| Company | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|
| Zeta | 160 | 105 | 70 | 145 |
| Delta | 65 | 45 | 100 | 145 |
| Sigma | 110 | 165 | 130 | 55 |
| Omega | 60 | 140 | 180 | 135 |
| Beta | 155 | 80 | 195 | 75 |
Example 1
By what percentage did Delta's production change from 2020 to 2023?
(a) +55.17% (b) +128.08% (c) +123.08% (d) −123.08%
- Delta: 65 (2020) → 145 (2023).
- Change = (145 − 65) ÷ 65 × 100 = 123.08%.
Answer: (c) +123.08%
Example 2
What is the average production of the five companies in 2022?
(a) 135 (b) 132 (c) 140 (d) 168.75
- Sum for 2022 = 70 + 100 + 130 + 180 + 195 = 675.
- Average = 675 ÷ 5 = 135.
Answer: (a) 135
Example 3
Which company had the highest total production over the four years?
(a) Sigma (b) Omega (c) Delta (d) Zeta
- Totals: Zeta 480, Delta 355, Sigma 460, Omega 515, Beta 505.
- Highest: Omega.
Answer: (b) Omega
Example 4
What is the ratio of Beta's production to Zeta's production in 2021?
(a) 17 : 21 (b) 21 : 16 (c) 16 : 22 (d) 16 : 21
- 80 : 105 = 16 : 21.
Answer: (d) 16 : 21
Example 5
What percentage of the total production in 2023 came from Delta (approximately)?
(a) 26.13% (b) 30.13% (c) 52.25% (d) 21.13%
- 145 ÷ 555 × 100 = 26.13%.
Answer: (a) 26.13%
Data set: Production table
| Company | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|
| Beta | 125 | 55 | 190 | 150 |
| Omega | 125 | 145 | 150 | 55 |
| Sigma | 70 | 150 | 120 | 185 |
| Delta | 95 | 145 | 170 | 50 |
| Zeta | 155 | 125 | 45 | 50 |
Example 6
By what percentage did Beta's production change from 2020 to 2023?
(a) +20% (b) +16.67% (c) −20% (d) +25%
- Beta: 125 (2020) → 150 (2023).
- Change = (150 − 125) ÷ 125 × 100 = 20%.
Answer: (a) +20%
Example 7
What is the average production of the five companies in 2023?
(a) 98 (b) 95 (c) 103 (d) 122.5
- Sum for 2023 = 150 + 55 + 185 + 50 + 50 = 490.
- Average = 490 ÷ 5 = 98.
Answer: (a) 98
Example 8
Which company had the highest total production over the four years?
(a) Omega (b) Delta (c) Beta (d) Sigma
- Totals: Beta 520, Omega 475, Sigma 525, Delta 460, Zeta 375.
- Highest: Sigma.
Answer: (d) Sigma
Example 9
What is the ratio of Zeta's production to Delta's production in 2022?
(a) 10 : 34 (b) 34 : 9 (c) 9 : 34 (d) 9 : 35
- 45 : 170 = 9 : 34.
Answer: (c) 9 : 34
Example 10
What percentage of the total production in 2023 came from Beta (approximately)?
(a) 34.61% (b) 30.61% (c) 61.22% (d) 25.61%
- 150 ÷ 490 × 100 = 30.61%.
Answer: (b) 30.61%
Data set: Production table
| Company | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|
| Omega | 145 | 145 | 170 | 85 |
| Alpha | 130 | 155 | 40 | 165 |
| Sigma | 190 | 100 | 55 | 50 |
| Delta | 200 | 40 | 145 | 155 |
| Zeta | 150 | 130 | 160 | 40 |
Example 11
By what percentage did Omega's production change from 2020 to 2023?
(a) −41.38% (b) +41.38% (c) −70.59% (d) −46.38%
- Omega: 145 (2020) → 85 (2023).
- Change = (85 − 145) ÷ 145 × 100 = -41.38%.
Answer: (a) −41.38%
Example 12
What is the average production of the five companies in 2021?
(a) 142.5 (b) 111 (c) 114 (d) 119
- Sum for 2021 = 145 + 155 + 100 + 40 + 130 = 570.
- Average = 570 ÷ 5 = 114.
Answer: (c) 114
Example 13
Which company had the highest total production over the four years?
(a) Alpha (b) Omega (c) Delta (d) Sigma
- Totals: Omega 545, Alpha 490, Sigma 395, Delta 540, Zeta 480.
- Highest: Omega.
Answer: (b) Omega
Example 14
What is the ratio of Omega's production to Sigma's production in 2023?
(a) 18 : 10 (b) 17 : 11 (c) 10 : 17 (d) 17 : 10
- 85 : 50 = 17 : 10.
Answer: (d) 17 : 10
Example 15
What percentage of the total production in 2021 came from Omega (approximately)?
(a) 25.44% (b) 50.88% (c) 20.44% (d) 29.44%
- 145 ÷ 570 × 100 = 25.44%.
Answer: (a) 25.44%
- Read all questions on a set before calculating – reuse totals.
- Approximate when options are far apart; compute exactly when they are close.
- Write intermediate numbers in a mini-table.
- Using the wrong base for percentage change.
- Ignoring units (thousands, crore, %).
- Confusing absolute and percentage changes.
Practice set
Use the chart or table for each set; about 90 seconds per question.
Practice data: Production table
| Company | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|
| Gamma | 115 | 120 | 90 | 70 |
| Zeta | 200 | 195 | 195 | 170 |
| Omega | 180 | 55 | 155 | 85 |
| Alpha | 140 | 185 | 65 | 160 |
| Sigma | 120 | 100 | 50 | 170 |
Q1. By what percentage did Omega's production change from 2020 to 2023?
(a) +52.78% (b) −111.76% (c) −52.78% (d) −57.78%
Q2. What is the average production of the five companies in 2022?
(a) 108 (b) 111 (c) 116 (d) 138.75
Q3. Which company had the highest total production over the four years?
(a) Zeta (b) Alpha (c) Gamma (d) Omega
Q4. What is the ratio of Zeta's production to Gamma's production in 2023?
(a) 18 : 7 (b) 17 : 8 (c) 7 : 17 (d) 17 : 7
Q5. What percentage of the total production in 2023 came from Omega (approximately)?
(a) 12.98% (b) 7.98% (c) 25.95% (d) 16.98%
Practice data: Production table
| Company | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|
| Beta | 45 | 110 | 135 | 195 |
| Sigma | 170 | 115 | 60 | 125 |
| Alpha | 55 | 150 | 100 | 170 |
| Zeta | 65 | 50 | 80 | 50 |
| Gamma | 145 | 115 | 55 | 45 |
Q6. By what percentage did Beta's production change from 2020 to 2023?
(a) +338.33% (b) +333.33% (c) +76.92% (d) −333.33%
Q7. What is the average production of the five companies in 2022?
(a) 83 (b) 107.5 (c) 91 (d) 86
Q8. Which company had the highest total production over the four years?
(a) Zeta (b) Sigma (c) Beta (d) Alpha
Q9. What is the ratio of Beta's production to Alpha's production in 2022?
(a) 27 : 20 (b) 20 : 27 (c) 28 : 20 (d) 27 : 21
Q10. What percentage of the total production in 2021 came from Beta (approximately)?
(a) 20.37% (b) 15.37% (c) 24.37% (d) 40.74%
Q1 – (c) −52.78%. Omega: 180 (2020) → 85 (2023). Change = (85 − 180) ÷ 180 × 100 = -52.78%.
Q2 – (b) 111. Sum for 2022 = 90 + 195 + 155 + 65 + 50 = 555. Average = 555 ÷ 5 = 111.
Q3 – (a) Zeta. Totals: Gamma 395, Zeta 760, Omega 475, Alpha 550, Sigma 440. Highest: Zeta.
Q4 – (d) 17 : 7. 170 : 70 = 17 : 7.
Q5 – (a) 12.98%. 85 ÷ 655 × 100 = 12.98%.
Q6 – (b) +333.33%. Beta: 45 (2020) → 195 (2023). Change = (195 − 45) ÷ 45 × 100 = 333.33%.
Q7 – (d) 86. Sum for 2022 = 135 + 60 + 100 + 80 + 55 = 430. Average = 430 ÷ 5 = 86.
Q8 – (c) Beta. Totals: Beta 485, Sigma 470, Alpha 475, Zeta 245, Gamma 360. Highest: Beta.
Q9 – (a) 27 : 20. 135 : 100 = 27 : 20.
Q10 – (a) 20.37%. 110 ÷ 540 × 100 = 20.37%.
- Units and base first
- % change on the old value
- Reuse totals
- Approximate wisely
