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Build an ISNOTERROR Formula Gate (NOT(ISERROR)) for Pre-Publish Workbook Checks
Construct the missing ISNOTERROR predicate with NOT(ISERROR(cell)) to score clean-row pass rates, block broken model tabs from release, and coordinate team sign-off.
Read the guide →Text & Data CleaningBuild Clean UTM & API Query URLs with Cross-Platform Percent-Encoding Formulas
Assemble campaign tracking and webhook URLs from spreadsheet columns while safely percent-encoding %, spaces, ampersands, and plus signs across Windows, Mac, and browser sheets.
Read the guide →Text & String CleaningBuild Dynamic mailto: Email Links With Subject, CC & URL-Encoded Body
Assemble RFC-6068 mailto: URIs from spreadsheet recipient, CC, subject, and body cells—replacing spaces with %20 via SUBSTITUTE so mail clients never truncate subjects at the first space.
Read the guide →TextBuild in-cell histograms and 10-slot progress bars with REPT
Scale large counts down by a divisor for compact REPT("|", ...) histograms, and clamp [====------] progress bars safely with MEDIAN.
Read the guide →Naval Architecture & Dry-Bulk StowageBulk Carrier Stowage Factor & Full-and-Down Formula
Calculate Vessel Ideal Stowage Factor V_hold / DWT_cargo, Maximum Loadable Tonnage MIN(DWT_cargo, V_hold / (SF * (1 + bs))), Deadweight Utilization, and Cube-Out vs Weigh-Out status.
Read the guide →Charts & Visual Data ModelingBullet Graph Formula: Stacked Qualitative Range Deltas, Actual Bar & Target Variance
Build Stephen Few’s compact dashboard Bullet Graph using incremental stacked qualitative bands (Poor, Satisfactory - Poor, Good - Satisfactory), Actual Performance % of Target, and Target Gap.
Read the guide →Industrial Organization & Pricing StrategyBulow-Coase Durable Monopoly Selling vs Leasing Formula
Quantify Ronald Coase’s (1972) and Jeremy Bulow’s (1982) two-period durable-goods monopoly price erosion and compare subgame-perfect outright selling profit against credible leasing.
Read the guide →Auction Theory & M&A StrategyBulow-Klemperer Extra-Bidder Auction Revenue Formula
Verify Jeremy Bulow & Paul Klemperer’s (1996) theorem that an (N + 1)-bidder zero-reserve auction (N/(N + 2))*V_max strictly beats an N-bidder Myerson optimal-reserve auction!
Read the guide →Math & TrigBundle and quote pricing with SUMPRODUCT (quantities, unit prices, and discounts)
Compute gross subtotals, line-discounted net totals, and total savings in a single cell with SUMPRODUCT—no line-extension column required.
Read the guide →Clinical Medicine & PhysiologyBurch-Wartofsky Point Scale (BWPS) Calculator: Thyroid Storm Diagnostic Criteria
Calculate Henry B. Burch and Leonard Wartofsky’s (1993) Thyroid Storm Point Scale (0–140 points) across Thermoregulatory Dysfunction, CNS Effects, GI-Hepatic Dysfunction, Tachycardia, Heart Failure, Atrial Fibrillation, and Precipitant History.
Read the guide →Well Control & Drilling Operations, Burkhardt (1961) Pipe-Tripping Surge & Swab HydraulicsBurkhardt Wellbore Surge & Swab Tripping Pressure Formula
Calculate Burkhardt Effective Annular Fluid Velocity Veff (m/s), Laminar Annular Surge/Swab Pressure Change (kPa), Running-In Surge EMW (SG), and Pulling-Out Swab EMW (SG).
Read the guide →Civil, Structural & Geotechnical EngineeringBurmister Two-Layer Pavement & Odemark Equivalent Thickness Formula: Deflection Factor F_2
Calculate two-layer elastic pavement surface deflection w_0 = F_2 * (1.5 * q * a / E_2) and Odemark’s Method of Equivalent Thickness h_e = f * h_1 * (E_1 / E_2)^(1/3) for stiff asphalt or base courses over soft subgrade.
Read the guide →Engineering & ScienceBurstein-Moss Shift: Degenerate Doping Optical Bandgap Widening
Calculate the conduction-band Pauli-blocking blue-shift ΔE_BM = 3.64645E-15 * n^(2/3) / m_eh^* (eV) and apparent optical bandgap E_g,opt = E_g0 + ΔE_BM in ITO and AZO transparent conducting oxides.
Read the guide →EngineeringButterworth Filter Gain, dB Roll-Off Attenuation & Bandpass Q-Factor
Calculate the magnitude and signed dB gain of an ideal analog Butterworth low-pass filter, distinguish finite-frequency gain from asymptotic roll-off, and calculate a separate bandpass Q.
Read the guide →Healthcare & Clinical CalculatorsBVAS v3 (Birmingham Vasculitis Activity Score, 0–63 Organ-Capped Scale)
Calculate the EULAR/FDA gold-standard ANCA-associated vasculitis trial endpoint BVAS v3 (0–63) by enforcing per-organ domain ceilings MIN(Max_Organ, Raw_Pts) and BVAS = 0 remission.
Read the guide →Monetary Economics & Sovereign RiskCagan Seigniorage Revenue & Peak Inflation Rate Formula
Calculate steady-state real seigniorage (pi + g_Y) * m_0 * EXP(-alpha * pi), Cagan’s revenue-maximizing inflation rate pi* = 1/alpha - g_Y, and maximum monetizable deficit.
Read the guide →Healthcare & Clinical CalculationsCAGE & CAGE-AID Alcohol / Substance Screening Score Calculator
Score John Ewing’s 4-item CAGE / CAGE-AID bedside screening questionnaire (Cut down, Annoyed, Guilty, Eye-opener; 0–4 points) with clinically significant threshold >= 2 or positive morning Eye-opener.
Read the guide →FinancialCAGR formula: calculate Compound Annual Growth Rate over multiple years
Compute the smoothed annualized growth rate with (EndValue / StartValue) ^ (1 / Years) - 1 and verify multi-year compounding.
Read the guide →Metalcasting & Steel Foundry Engineering, Caine (1948) AFS Hyperbolic Riser Feeding LawCaine Sand-Casting Riser Freezing-Ratio & Yield Formula
Calculate Actual Riser-to-Casting Modulus Freezing Ratio x = Mr/Mc, Volume Ratio y = Vr/Vc, Caine Hyperbolic Minimum Soundness Ratio xmin, and Mold Casting Yield (%).
Read the guide →Statistical & Clinical AnalysisCalculate & Plot Regression Residuals: Predicted Y, Residual Error & Outlier Flag
Build a linear regression Residual Plot table without Analysis ToolPak: compute Predicted Y_hat = INTERCEPT + SLOPE * X, Signed Residual e_i = Y_i - Y_hat, and Regression Standard Error s_e = SQRT(SSE / (n - 2)).
Read the guide →FinanceCalculate a Complete Four-Period Hull Moving Average and Efficiency Ratio
Calculate two consecutive raw Hull values and their final weighted smoothing, then compare net change with total absolute movement using Kaufman’s efficiency ratio.
Read the guide →FinancialCalculate a fictional two-rate marginal charge with MIN and MAX
Split an amount at a threshold, apply one rate to each slice, and compare rounded charges with the underlying blended rate.
Read the guide →Math & TrigCalculate a ratio from two numbers: simplified whole-number (16:9) and N:1
Reduce positive integer dimensions to lowest ratio terms with GCD, or express a ratio with a nonzero denominator in N:1 form.
Read the guide →Math & TrigCalculate a running total (cumulative balance) that skips blank rows
Use an expanding SUM range for cumulative balances and suppress output on truly empty rows.
Read the guide →Date & TimeCalculate age from birthdate: exact years and months as of any date
Compute completed age in whole years and remaining months from a date of birth without off-by-one rounding errors.
Read the guide →Date & TimeCalculate business work hours between two dates and times (SLA timer)
Count only business-day work hours (e.g., 09:00–17:00 Mon–Fri) between ticket open and close timestamps using NETWORKDAYS.
Read the guide →Lookup & ReferenceCalculate Carrier Shipping Cost by Weight Ceiling & Zone (2D XLOOKUP Mode 1)
Look up parcel shipping rates from a carrier Zone x Max-Weight rate card using nested XLOOKUP with match_mode = 1 (exact match or next larger weight ceiling)—fixing VLOOKUP's next-smaller bracket bug!
Read the guide →HealthcareCalculate Clinical and Full Rockall Scores in a Spreadsheet
Practice validated category inputs, missing-data guards and separate pre-endoscopy and full Rockall totals using fictional data.
Read the guide →FinancialCalculate Coast FI number: invested balance needed to coast to retirement
Divide annual retirement spending by a chosen withdrawal-rate assumption and discount back to today using PV or (1 + RealReturn)^Years.
Read the guide →FinancialCalculate cumulative loan interest and principal for any year or period range
Compute exact Year-1, Year-2, or full-term principal and interest paid from remaining FV balances—without a 360-row schedule.
Read the guide →Date & TimeCalculate date overlap in days: find shared days between two bookings or projects
Count inclusive overlapping days between any two date ranges in one line using MAX(0, MIN(End1, End2) - MAX(Start1, Start2) + 1).
Read the guide →Date & TimeCalculate Days Open & Invoice Age Status (Open vs Closed Items)
Calculate elapsed calendar days as of an explicit report date, cap aging at a valid closure date, and label active items using a configurable age threshold.
Read the guide →Lookup & ReferenceCalculate difference from last non-blank entry in a sparse log (TAKE & FILTER)
Subtract the previous numeric reading in source-row order, preserving gaps and numeric zero.
Read the guide →Date & TimeCalculate due date by category or SLA priority (business or calendar days)
Look up turnaround days by ticket priority or vendor payment tier with XLOOKUP and add business days via WORKDAY.
Read the guide →FinanceCalculate Effective Hourly Pay Rate (Weighted Shift Pay vs Simple Mean)
Compare gross earnings per worked hour with the simple average of shift rates, and calculate an illustrative gap to a chosen target without confusing it with a statutory payroll calculation.
Read the guide →Date & TimeCalculate expiration dates and days remaining (days, months, or month-end)
Add fixed shelf-life days, calendar warranty months (EDATE), or end-of-month expirations (EOMONTH), and flag expired items.
Read the guide →EngineeringCalculate GPS distance between latitude and longitude coordinates
Compute great-circle distance in kilometers or miles with spherical law of cosines—clamping ACOS inside [-1, 1] for identical points.
Read the guide →StatisticalCalculate Grubbs G and an upper-end Dixon gap ratio
Calculate two single-extreme statistics for six numeric observations, with explicit assumptions and no automatic deletion of data.
Read the guide →Date & TimeCalculate hours between two times (including overnight night shifts)
Wrap EndTime - StartTime in MOD(..., 1) * 24 so shifts crossing midnight return 8.5 positive hours instead of -15.5.
Read the guide →Date & TimeCalculate hours that overlap a specific time window (shift differential)
Measure exact hours of a work shift or booking that fall inside an evening differential or peak-rate time block using MAX and MIN.
Read the guide →Lookup & ReferenceCalculate Letter Grades (A+ to F) from Numeric Scores (XLOOKUP & VLOOKUP)
Assign A+ through F using an editable illustrative plus/minus scale, validate scores and cutoffs, and compare XLOOKUP with ascending-table VLOOKUP.
Read the guide →FinancialCalculate loan interest and principal paid in any given year (closed-form FV)
Estimate interest and principal during a selected full 12-month loan year using PMT and FV.
Read the guide →StatisticalCalculate Midrange and Tukey Trimean: extreme vs outlier-resistant centers
Compute the Midrange (MIN + MAX) / 2 and contrast it with Tukey's outlier-resistant Trimean (Q1 + 2*Median + Q3) / 4.
Read the guide →FinancialCalculate monthly savings needed to reach a financial goal (PMT)
Pass GoalAmount as the 4th fv argument of PMT (with existing savings as negative pv) to solve required monthly contributions.
Read the guide →Financial & AccountingCalculate Original Loan Amount & Borrowing Limit from Monthly Payment (PV)
Back-solve the original loan principal or maximum affordable loan balance from a fixed periodic payment, annual interest rate, and term in months using PV.
Read the guide →Math & StatisticalCalculate Percent Absent & Attendance Rate Ignoring Unmarked Days
Compute exact student or employee absence percentage COUNTIF(B2:G2, "A") / COUNTA(B2:G2) and present/excused attendance rate while ignoring blank unrecorded future sessions.
Read the guide →Date & TimeCalculate percent of year complete (leap-year exact pacing)
Divide ordinal day-of-year by exact calendar days in that year (365 or 366) to benchmark annual quota and budget pacing.
Read the guide →StatisticalCalculate quintiles (20%, 40%, 60%, 80%) and assign 1–5 quintile buckets
Compute percentile cutoffs and assign values to five threshold-based bands.
Read the guide →Date & TimeCalculate retirement, benefit eligibility, and equity cliff dates (EDATE & EOMONTH)
Calculate illustrative age milestones and month-based waiting dates with explicit calendar conventions.
Read the guide →StatisticalCalculate RMSE and MSE: Root Mean Squared Error forecast accuracy formula
Score demand and revenue forecasts in a single formula without helper columns using SQRT(SUMPRODUCT((Actual - Forecast)^2) / ROWS(Actual)).
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