DI — Tables

Tabular DI is the most data-dense set type: rows and columns of raw numbers with no visual shortcut, so it rewards calculation discipline and selective reading. In CAT, DI+LR together make ~4–6 sets of ~22 questions; a well-chosen table set is a high-accuracy scoring block.

What a table demands

Everything is exact numbers, so the traps are (a) reading the wrong cell, (b) mixing up row vs column totals, and (c) over-computing when an estimate suffices. Speed comes from computing only what a question needs.

Core operations

Operation	Formula
Percentage share	(part ÷ whole) × 100
Percentage change	((new − old) ÷ old) × 100
Ratio of two cells	a : b (simplify)
Average of a row	(sum of entries) ÷ (count)
Growth over years	compare consecutive column values

Method

1. Spend 20–30s reading headers, units, and footnotes — misreading units (₹ lakh vs ₹ crore) kills a whole set.
2. For each question, locate the exact cells; don't scan the whole table.
3. Estimate first; compute exactly only when options are close.
4. Reuse partial totals across questions in the same set.

Exam Tricks & Tips

• 🎯 Read the unit line first. "in thousands", "% of total", "₹ crore" — a unit slip invalidates every answer in the set.
• 🎯 Compute only what's asked. Never total the whole table if a question needs two cells.
• 🎯 Percentage change uses the OLD value as base, not the new one — the single most common table error.
• 🎯 Compare fractions without full division. To rank a/b vs c/d, cross-multiply (a·d vs c·b) instead of computing both decimals.
• 🎯 Bank reusable subtotals. A column total you computed for Q1 often answers Q3 — jot it down.
• ❌ Common mistake: confusing "percentage point change" with "percentage change" — a rise from 20% to 25% is +5 percentage points but +25% in relative terms.

Expected exam pattern

1–2 table sets of 3–5 questions each within DILR. Mix of MCQ and TITA. Questions ask share, change, ratio, rank, and "how many satisfy a condition". Reward: accuracy under time; the data is exact, so no ambiguity — only arithmetic risk.

Quick recap

Read headers/units first, fetch only the cells you need, use OLD value as the base for percentage change, compare fractions by cross-multiplication, and reuse subtotals. Tables are exact — your only enemy is careless arithmetic.

Cover the answer, recall, then check. 12 cards on tabular DI.

Q1. What is the first thing to read in a table set?
A1. Headers, units, and footnotes (e.g. ₹ lakh vs ₹ crore, "in thousands").

Q2. Percentage share formula?
A2. (part ÷ whole) × 100.

Q3. Percentage change formula — and the base?
A3. ((new − old) ÷ old) × 100 — the OLD value is the base.

Q4. How do you rank two fractions a/b and c/d quickly?
A4. Cross-multiply: compare a·d with c·b — no full division needed.

Q5. Difference between percentage points and percentage change?
A5. 20%→25% is +5 percentage points but +25% relative change.

Q6. Should you total the whole table for a two-cell question?
A6. No — compute only what the question needs.

Q7. Why note reusable subtotals?
A7. A total computed for one question often answers another in the same set.

Q8. Average of a row?
A8. (sum of the row's entries) ÷ (number of entries).

Q9. Biggest reading trap in tables?
A9. Fetching the wrong cell or confusing row totals with column totals.

Q10. When should you compute exactly vs estimate?
A10. Estimate first; compute exactly only when the options are close.

Q11. A unit slip affects how much of the set?
A11. Potentially every answer — units apply across the whole table.

Q12. How many table sets appear in CAT DILR?
A12. Typically 1–2 sets of 3–5 questions each.

Tables are the rawest DI form — no visual to interpret, just rows and columns of numbers. That's their danger: everything is given, so students dive in and calculate blindly, drowning in arithmetic the question never actually required. On the CAT, table DI is won by reading the structure before touching a single number and by computing only what's asked.

What this tests

Structured data navigation — orienting to what each row and column represents, extracting the exact cells a question needs, and doing minimal calculation to answer.

The method

Beginner — decode the table's architecture first

Spend 20–30 seconds mapping: What do rows represent? What do columns represent? What are the units (absolute numbers, percentages, ₹ crore, thousands)? Is there a totals row/column? Misreading units ("₹ in lakhs" vs "₹ in crores") is the single biggest table blunder. Note whether values are cumulative or period-wise.

Intermediate — read the question, then fetch only those cells

Every table question points to a specific subset — one row, one column, or an intersection. Identify the exact cells before calculating. If a question asks for the year with the highest growth, you need consecutive-year comparisons, not every cell. Resist computing the whole table "to be safe" — it wastes minutes.

Advanced — the FAST CAT approach: compare, don't compute

Most table questions ask "which is largest / smallest / closest" — these are comparison questions, and comparisons rarely need exact values.

• To compare fractions/ratios across rows, use cross-multiplication or approximate percentages, not decimal division.
• For "which grew fastest", eyeball the ratio new/old; the biggest jump is often visible without precise math.
• Keep a running rank, not exact figures.

Also exploit totals: if a total is given, a missing part = total − sum of others (faster than re-adding). And when a question spans multiple cells, set up the full expression symbolically first, cancel common factors, then plug numbers.

Worked example

A table gives revenue (₹ crore) for 4 firms over 3 years. Question: Which firm had the highest percentage growth from Year 1 to Year 3?
Firm A: 200 → 260 (+30%), Firm B: 150 → 210 (+40%), Firm C: 320 → 400 (+25%), Firm D: 90 → 135 (+50%).
Don't compute exact CAGRs. Just ratio Year3/Year1: A = 1.30, B = 1.40, C = 1.25, D = 135/90 = 1.50. Highest ratio = Firm D (+50%). Notice D had the smallest absolute values — a classic trap where the biggest firm (C, largest revenue) has the lowest growth. Answer: D.

CAT relevance

Tables anchor many DILR sets, often combined with a caselet or a second data source. The CAT rewards set-selection: a clean, well-labelled table with straightforward questions is often the easiest set to attempt first. The "compare don't compute" reflex here saves the minutes you'll need on the harder logical sets.

Speed tricks & shortcuts

• Map rows, columns, and units before reading questions — 30 seconds that prevents 3-minute errors.
• Comparisons need ratios, not exact division — cross-multiply or approximate.
• Use given totals to back out missing values (total − others).
• Mnemonic — "Read the frame before the figures."
• Circle the units — lakhs vs crores, % vs absolute — the top source of wrong answers.

Key formulas

• Read the exact cell; totals across rows/columns give sums.
• Percentage share = (cell/row or column total)×100.
• Percentage change between periods = (new − old)/old ×100.
• Average of a row/column = sum/count.
• Ratios compare two cells directly.

Usage: compute row/column totals first, then percentages and ratios off them.

Worked Example

Problem: The table shows units sold (in thousands) by four products across three years.

Product	2021	2022	2023
A	40	50	65
B	30	30	24
C	20	28	35
D	60	66	72

(a) Which product had the highest percentage growth from 2021 to 2023? (b) What was product D's share of total sales in 2023 (nearest %)?

Solution:
(a) Percentage growth = (2023 − 2021) / 2021 × 100. Compute for each product:

• A: (65 − 40)/40 = 25/40 = 62.5%
• B: (24 − 30)/30 = −6/30 = −20% (a decline)
• C: (35 − 20)/20 = 15/20 = 75%
• D: (72 − 60)/60 = 12/60 = 20%
  The largest is C at 75%. Note the trap: A grew by more UNITS in absolute terms (25 vs C's 15), but the question asks percentage growth, where C wins because it grew from a smaller base. Always match the metric asked (absolute vs percentage).

(b) D's share in 2023 = D's 2023 sales / total 2023 sales × 100.
Total 2023 = 65 + 24 + 35 + 72 = 196 (thousand).
Share = 72 / 196 × 100 = 7200/196 ≈ 36.7% ≈ 37%.
Quick check by approximation: 72/196 ≈ 72/200 = 36%, and since the denominator is slightly below 200, the true value is a touch higher (~37%) — consistent.

Answer: (a) Product C, with 75% growth (highest percentage, even though A had the largest absolute increase). (b) D's 2023 share = 72/196 ≈ 37%.