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Count Item Occurrences Across Multiple Worksheets or Regional Logs
Total how many times a SKU, employee ID, or ticket code appears across separate regional tabs or log blocks without #REF! 3D-COUNTIF errors.
Read the guide →TextCount line breaks, build multiline cells & extract specific lines with CHAR(10)
Count line breaks and lines inside Alt+Enter cells using LEN - LEN(SUBSTITUTE(A2, CHAR(10), "")), extract the Nth line via TEXTSPLIT, and join lines with CHAR(10).
Read the guide →Statistical & Conditional CountingCount Matches Between Two Columns: Row-by-Row Alignment vs. Set Overlap
Distinguish exact same-row positional matches, case-sensitive row matches, and unordered cross-column membership counts while preventing empty padding rows from inflating match totals.
Read the guide →Date & Time FormulasCount New (First-Time) Customers Per Month (MINIFS & COUNTIFS)
Distinguish genuine first-time customer acquisitions from repeat monthly orders by tagging each customer’s earliest purchase date with MINIFS and counting monthly cohort entries with COUNTIFS and EOMONTH.
Read the guide →StatisticalCount non-blank and missing cells by category (COUNTIFS data completeness %)
Audit CRM or vendor master-data completeness per region using COUNTIFS with "<>" (populated) and "" (blank) criteria.
Read the guide →Conditional AggregationCount Non-Blank Cells That Do Not Contain Any Blocklisted Substrings
Count clean transaction or SKU rows that exclude multiple unwanted substrings simultaneously using multi-criteria COUNTIFS wildcard exclusions and row-level SEARCH flags.
Read the guide →Text & StringCount Numeric Digits (0–9) Inside an Alphanumeric Text String
Count how many numeric digits (0–9) appear anywhere inside a mixed serial number, SKU, or password string by subtracting digit-stripped length from LEN(A2).
Read the guide →TextCount occurrences of a specific word in a cell or range (whole-word safe)
Count case-insensitive space-delimited tokens or non-overlapping literal substrings in a small text range.
Read the guide →Data Validation & AuditingCount Positive, Negative, Numeric & Formula-Error Cells in a Ledger Range
Reconcile mixed audit columns containing gains, losses, zeros, text notes, and #DIV/0! errors using COUNTIF(">0"), COUNTIF("<0"), COUNT, and --ISERROR(B2) flags.
Read the guide →Date & TimeCount Records by Age Bracket Directly from Birthdates (EDATE + COUNTIFS)
Count how many people fall into age bands like 25–34 or 35–44 as of a valuation date without adding a helper age column by translating age bounds into exact EDATE birth-date cutoffs.
Read the guide →Conditional AggregationCount Rows Meeting Internal Column-vs-Column Criteria (SUMPRODUCT)
Count table rows where one column exceeds or precedes another column on the same row—such as Actual > Budget AND Ship_Date <= Due_Date—using Boolean SUMPRODUCT.
Read the guide →Statistical & Conditional CountingCount Rows Not Equal to Multiple Criteria (COUNTIFS Multi-Exclusion)
Count active operational rows that simultaneously exclude Cancelled, Refunded, and Blank status entries—Avoiding the classic OR("<>A", "<>B") logical trap.
Read the guide →Conditional AggregationCount Rows Where Column C Exceeds Column B (Row-by-Row SUMPRODUCT)
Count how many table rows satisfy an internal column-to-column test (such as Actual > Budget or Shipped_Days > SLA_Days) and sum the excess variance in one formula using SUMPRODUCT(--(C2:C6 > B2:B6)) without helper columns.
Read the guide →StatisticalCount rows with at least N matching values across columns (COUNTIF & FILTER)
Count or list records with at least N Pass labels across four training modules, using a per-row COUNTIF helper.
Read the guide →StatisticalCount sold vs. remaining seats or inventory and sell-through percentage
Count assigned and available slots in a fixed six-row roster and calculate its assigned fraction.
Read the guide →TextCount specific characters across a range of cells
Count every hashtag, comma, or letter across an entire column at once by combining TEXTJOIN, LEN, and SUBSTITUTE.
Read the guide →TextCount specific characters in a cell: case-sensitive and case-insensitive
Count how many times a delimiter or letter appears inside a string by comparing original text length against SUBSTITUTE length.
Read the guide →Date & TimeCount specific weekdays between two dates (e.g., Mondays in a month)
Jump to the first matching weekday on or after StartDate using MOD and WEEKDAY, then divide the remaining span by 7.
Read the guide →Text & CleaningCount Text-Stored Numbers With Leading Zeros (ZIP, Routing & Badge Audit Formula)
Detect and count text-stored numeric strings carrying leading zeros (such as "07030" or "0042") without false positives on true numbers, "0", decimals ("0.75"), or alphanumeric codes.
Read the guide →Date & TimeCount Times Within a Specific Time Window (Daytime & Overnight COUNTIFS)
Count arrival, call, or transaction times between Start_Time and End_Time—handling both standard daytime windows (09:00–17:00) and cross-midnight graveyard shifts (22:00–06:00).
Read the guide →TextCount total characters in a range (with or without spaces)
Join an entire column with empty delimiter "" inside TEXTJOIN and measure LEN once—no helper column required.
Read the guide →Text & Data CleaningCount Total Words Across a Multi-Cell Range Safely (Blank & Space Guards)
Count total space-delimited words across an entire column or block of notes—without inflating counts on blank cells, double spaces, or space-only entries—using TRIM, TEXTJOIN, LEN, and SUBSTITUTE.
Read the guide →Date & TimeCount unique dates while ignoring timestamps (INT + UNIQUE)
Strip fractional clock times from audit timestamps with INT before counting distinct active calendar days with UNIQUE.
Read the guide →Lookup & ReferenceCount Unique Numeric Values Separately From Unique Text Values in a Mixed Column
Count distinct numbers and distinct non-blank text labels independently in mixed-type ranges using UNIQUE, FILTER, ISNUMBER, and ISTEXT with empty-set guards.
Read the guide →Conditional AggregationCount Unique Rows or Columns Containing a Specific Value (Avoiding Double-Counts)
Count how many distinct rows or distinct columns in a 2D inspection matrix contain at least one "Fail" without double-counting multiple failures on the same row or station!
Read the guide →Dynamic arraysCount unique values in a column while ignoring blank cells
Pair UNIQUE with FILTER and ROWS to count distinct customers or SKUs without counting empty rows as an extra item.
Read the guide →Dynamic ArraysCount unique values with criteria (COUNTUNIQUEIFS pattern)
Count distinct customers or SKUs inside a filtered region or date window using FILTER, UNIQUE, and ROWS with a zero-match guard.
Read the guide →Conditional AggregationCount Visible Rows & Filtered Criteria Matches (SUBTOTAL 103 & Helper Column)
Count visible non-empty records with SUBTOTAL(103, range) and pair a row-level visibility indicator (=SUBTOTAL(103, A2)) with SUMPRODUCT to count visible rows matching specific criteria.
Read the guide →Text & String ManipulationCount Whole-Word Occurrences in a Cell Without Partial Substring False Positives
Count how many times a standalone target word appears inside a sentence or log message by normalizing punctuation to spaces and padding word boundaries before measuring LEN - LEN(SUBSTITUTE).
Read the guide →Math & TrigCount with OR criteria: same-column addition vs two-column overlap
Add COUNTIF calls for mutually exclusive values in one column, and subtract COUNTIFS overlap when testing OR across two columns.
Read the guide →TextCount words in a cell: handle extra spaces and blank cells safely
Count space-separated words after normalizing repeated ordinary spaces, including empty cells and formulas returning empty text.
Read the guide →Date & TimeCount Working Days With Custom Weekend Masks (Closed-Form NETWORKDAYS.INTL)
Calculate net working days between two dates under any custom 2-day weekend schedule (such as Friday–Saturday or Sunday–Monday) and subtract non-weekend public holidays using exact modular arithmetic.
Read the guide →Streaming Algorithms & Data EngineeringCount-Min Sketch Sizing & Birthday Collision Formula
Size Cormode-Muthukrishnan Count-Min Sketch tables via width CEILING(EXP(1)/eps, 1) and depth CEILING(LN(1/delta), 1), and audit Birthday-Paradox hash collisions 1 - EXP(-n*(n - 1)/(2*M)).
Read the guide →Counting and missing dataCOUNT, COUNTA and COUNTBLANK: what counts as an empty cell?
Audit a small measurement log. Distinguish numeric readings, entered notes, truly empty cells and formulas that look blank.
Read the guide →Lookup & ReferenceCount, sum and find the maximum in a selected column with CHOOSECOLS
Select a metric by its unique header, then use SUMPRODUCT to count qualifying rows or total a region and MAX for all regions.
Read the guide →MathCOUNTIF & SUMIF Across Non-Contiguous Ranges (Additive & VSTACK)
Count matching rows and sum quantities from two separate blocks, with literal criteria and a dynamic-array alternative.
Read the guide →Checking repeated recordsCOUNTIF in Excel: flag repeated IDs before changing the data
Count repeated booking identifiers, keep blank IDs out of the flags, and distinguish repeated rows from extra copies.
Read the guide →Dates and reportingCOUNTIFS between dates: count a full month, including timestamps
Count open repair tickets received in March. Use an inclusive start and an exclusive next-month boundary so a ticket arriving late on the final day is included.
Read the guide →Counting recordsCOUNTIFS: count open orders above a minimum amount
Count qualifying orders without adding their values. This example combines an order status with a minimum amount and checks what happens exactly at the threshold.
Read the guide →FinancialCoupon-date bond valuation with PV: par, discount and premium
Price a simplified fixed-coupon bond on a coupon date and compare its current yield with yield to maturity.
Read the guide →Antitrust Economics & M&A StrategyCournot Merger Paradox & 80% Threshold Formula
Prove Salant, Switzer & Reynolds’s (1983) Cournot Merger Paradox: without cost synergies, merging M of N symmetric Cournot rivals loses money unless M >= 80% of the industry!
Read the guide →Industrial Organization & Antitrust EconomicsCournot Oligopoly Nash Price and Cowling-Waterson HHI Lerner Formula
Solve N = 3 asymmetric Cournot-Nash equilibrium price P* = (a + SUM c_i) / (N + 1), firm outputs q_i = (P* - c_i) / b, and verify Cowling and Waterson’s HHI / |e_D| markup identity.
Read the guide →LogicalCourse & onboarding completion matrix formula ("Complete", "In Progress 3/4", "Not Started")
Summarize explicit X completion marks for four modules and calculate the share of listed learners with every module marked.
Read the guide →Counting & Conditional AggregationCourse Completion & Compliance Pass-Rate Summary With COUNTIFS
Calculate LMS training compliance rates (%) requiring both Status = "Completed" and Exam Score >= Passing Cutoff using COUNTIFS(C2:C7, "Completed", D2:D7, ">=" & F2) / COUNTA(A2:A7).
Read the guide →FinancialCovered Interest Rate Parity (CIRP): FX forward rate & forward points formula
Compute an illustrative FX forward parity benchmark using simple annual rates, a common day basis and a stated quote convention.
Read the guide →Health & FitnessCox Survival 10-Year Cardiovascular Risk (Framingham / PCE Formula)
Evaluate 10-year ASCVD / Framingham Cox proportional-hazards event probability Risk_10yr = 1 - (S_0 ^ EXP(Individual_BetaX - CohortMean_BetaX)) and ACC/AHA risk-tier thresholds.
Read the guide →Financial ModelingCox-Ingersoll-Ross (CIR) Short-Rate Zero-Coupon Bond Price, Yield & Feller Condition
Price affine zero-coupon bonds under the Cox-Ingersoll-Ross (1985) square-root diffusion dr = a(b - r)dt + sigma*sqrt(r)dW with closed-form A(T), B(T), and Feller positivity ratio 2ab / sigma^2.
Read the guide →Actuarial Science & Insurance RiskCramér-Lundberg Ruin Probability & Adjustment Coefficient R
Calculate relative security loading theta, Cramér-Lundberg adjustment coefficient R = theta / ((1 + theta) * mu), Lundberg ruin bound EXP(-R * u_0), and exact exponential ruin probability.
Read the guide →StatisticalCramer's V effect size & Chi-Square contingency table association formula
Calculate Chi-Square SUM((O - E)^2 / E) and sample-size-adjusted Cramer's V = SQRT(ChiSq / (N * MIN(r - 1, c - 1))) for categorical cross-tabulations.
Read the guide →Aerospace Cost Estimating & OperationsCrawford Unit vs Wright Learning Curve Formula
Avoid a 44% unit-cost bidding error by distinguishing J. R. Crawford’s Incremental Unit Learning Curve Y_n = T_1 * n^b from T. P. Wright’s Cumulative-Average Unit Difference T_1*(n^(1+b) - (n-1)^(1+b)).
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