Data Interpretation
Data Interpretation
Read and analyse data from tables, bar charts, pie charts, line graphs, and caselets, then apply percentage, ratio, or change formulas. DI is the single highest-weight section in IBPS PO and SBI PO (15\u201320 marks) and carries similar weight in SSC CGL Tier II. Speed on approximation and ratio shortcuts directly determines the score.
Key Idea
Identify the 'total' and the 'unit' of the data before touching the options — 90 % of DI errors come from reading the wrong row, column, or scale.
Core Formulas
Percentage Share (Table / Bar DI)
Percentage = (Part / Whole) × 100
Identify the correct total from column/row headers first, then divide the part by that total to get the share.
Bar Chart Visual Ratio
Ratio = Height of Bar A : Height of Bar B (no absolute values needed)
Compare bar heights directly for ratio questions \u2014 skip absolute-value computation when both bars share the same scale.
Pie Chart Sector Value
Sector Value = (Angle / 360) × Total | Percentage = Angle / 3.6
Convert a pie sector's angle to an absolute value or a percentage; compute the total once and reuse it for every question in the set.
Percentage Change (Line Graph DI)
% Change = ((New − Old) / Old) × 100
For trend or growth-rate questions on line graphs; check the sign first — a negative result means decrease, which immediately eliminates any option greater than the original value.
Caselet — Extract & Label
Convert text → table: rows = entities, columns = attributes; mark given vs. computed values
Before solving any paragraph-based DI set; writing out the extracted numbers as a mini-table prevents misreads and saves time across all sub-questions.
Relevant Exams
DI is the single highest-weightage section in banking (IBPS PO / SBI PO Prelims & Mains) and carries 15–20 marks in SSC CGL Tier 2. Speed on approximation and ratio shortcuts directly determines the score.