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Calculate sales commission: flat-tier IFS vs marginal progressive brackets
Implement both retroactive flat-rate commission tiers with IFS and cliff-free marginal bracket commissions with MIN and MAX.
Read the guide →Date & TimeCalculate stopped dwell time from a fleet GPS timestamp & milepost log
Estimate time in unchanged-location intervals from an ordered timestamp and milepost log, with explicit sampling assumptions.
Read the guide →StatisticsCalculate Student & Workforce Absence Rate (%) & Chronic Absence Flag
Calculate absence rates from validated P, T, A and E codes, distinguish missing records from zero absence, and compare a recorded-period rate with an illustrative threshold.
Read the guide →Date & TimeCalculate the Nth or last weekday of a month
Build a recurring monthly schedule and detect when a requested fifth weekday does not exist.
Read the guide →FinancialCalculate VAT or sales tax: add tax to net and reverse gross to net
Compute tax-inclusive gross prices from net amounts and extract exact embedded VAT and net revenue from tax-inclusive totals.
Read the guide →StatisticalCalculate win, loss, and tie totals (plus win % and league points)
Summarize raw match scores into Wins, Losses, Ties, Win Percentage, and 3-1-0 league points while ignoring unplayed fixtures.
Read the guide →Charts & Data VisualizationCalculation of Pi in Spreadsheets: Unit-Circle Scatter Dartboard & Archimedes Bounds
Approximate Pi visually using a Monte Carlo unit-quarter-circle scatter indicator (X^2 + Y^2 <= 1 -> Pi_hat = 4 * Hits / N) and bound Pi deterministically via Archimedes’ inscribed/circumscribed regular N-gon perimeters.
Read the guide →Civil, Structural & Geotechnical EngineeringCalifornia Bearing Ratio (CBR) & Subgrade Resilient Modulus M_R Formula (ASTM D1883)
Calculate ASTM D1883 California Bearing Ratio CBR (%) at 0.10-in (1,000 psi standard crushed rock) and 0.20-in (1,500 psi) piston penetrations, and convert CBR into AASHTO MEPDG Subgrade Resilient Modulus M_R = 2555 * CBR^0.64.
Read the guide →Industrial Instrumentation, Metrology & Process ControlCallendar-Van Dusen Pt100 RTD Resistance Formula
Calculate IEC 60751 Platinum RTD Resistance R(T) = R_0 * (1 + A*T + B*T^2) for T >= 0 °C, compare against Naive Linear Alpha (0.00385/°C) Approximation, and quantify Uncalibrated Temperature Drift (°C).
Read the guide →FinancialCalmar-style return/drawdown ratio and a CAPM excess-return worksheet
Compare a supplied annualized return with observed maximum drawdown and calculate a same-period return residual against a supplied CAPM beta.
Read the guide →Oncology Pharmacy & Clinical PharmacokineticsCalvert Carboplatin AUC & Capped GFR Dose Formula
Calculate Total Carboplatin Dose (mg, NOT mg/m^2!) via A.H. Calvert’s Formula Target_AUC * (MIN(125, GFR) + 25), Pharmacy Vial Volume (mL), and Overdose Milligrams Prevented by the FDA/CTEP 125 mL/min GFR Cap.
Read the guide →Macroeconomics & DSGE ModelingCalvo Staggered Pricing & New Keynesian Phillips Curve Slope
Derive mean price duration 1/(1 - theta), structural NKPC marginal-cost slope kappa = (1 - theta)*(1 - beta*theta)/theta, and quarterly inflation pi_t.
Read the guide →Emerging Markets & Open-Economy MacroeconomicsCalvo Sudden-Stop Absorption Cut & RER Jump Formula
Calculate Guillermo Calvo’s (1998, 2004) sudden-stop Tradable Absorption Contraction CAD / omega_T and required Real Exchange Rate Depreciation (1 - CAD / omega_T)^(-1 / xi) - 1.
Read the guide →Water Treatment Engineering, Rapid Mix & Tapered FlocculationCamp-Stein Velocity Gradient (G) & Camp Number (Gt) Formula
Calculate Flocculation Basin RMS Velocity Gradient G (s^-1), Detention Time t (seconds), Dimensionless Camp Number G*t, and Specific Mixing Power Input (W/m³).
Read the guide →Quantitative FinanceCampbell-Shiller CAPE Ratio & Excess CAPE Yield (ECY) Formula
Calculate the 10-year inflation-adjusted Cyclically Adjusted P/E ratio CAPE = Real_Price / AVERAGE(Real_EPS_10y) and Shiller’s Excess CAPE Yield ECY = (1 / CAPE) - Real_10Y_Bond_Yield.
Read the guide →Quantitative Finance & ForecastingCampbell-Thompson Out-of-Sample R-Squared and Truncated Forecast
Compute Campbell and Thompson’s (2008) out-of-sample R^2_OS = 1 - SSE_model / SSE_hist and verify how zero-truncating negative risk-premium forecasts MAX(0, r_hat) turns negative R^2_OS positive.
Read the guide →Healthcare & ClinicalCanadian C-Spine Rule (CCR): 3-Step Cervical Spine Imaging Decision Formula
Evaluate Ian Stiell's 3-step Canadian C-Spine Rule (High-Risk Factor -> Low-Risk Factor Allowing Assessment -> Active 45-Degree Left/Right Neck Rotation) for alert, stable blunt trauma patients (GCS = 15).
Read the guide →Healthcare & ClinicalCanadian CT Head Rule (CCHR) Minor Head Injury Decision Formula
Evaluate Ian Stiell’s validated Canadian CT Head Rule across 5 High-Risk neurosurgical criteria and 2 Medium-Risk brain-injury criteria for adults (GCS 13–15) with witnessed LOC, amnesia, or disorientation.
Read the guide →Meteorology, Occupational Hygiene & Environment Canada HumidexCanadian Humidex Vapor Pressure & Thermal Discomfort Formula
Calculate Environment and Climate Change Canada (MSC) Actual Water Vapor Pressure e (hPa) from Dew Point via Clausius-Clapeyron, Humidex Increment h = 0.5555*(e - 10), Total Humidex Score, and MSC Public Heat-Advisory Tier.
Read the guide →Financial & AccountingCandlestick (OHLC) Chart Formula: Real Body, Upper & Lower Wicks & Doji Body Ratio
Validate Open-High-Low-Close (OHLC) price bars and compute Candlestick Real Body = Close - Open, Upper Shadow = High - MAX(Open, Close), Lower Shadow = MIN(Open, Close) - Low, and Body-to-Range ratio.
Read the guide →EngineeringCantilever Beam Tip Deflection, Rotation Angle & Root Bending Stress
Calculate Euler-Bernoulli cantilever beam tip deflection delta = F*L^3 / (3*E*I), end slope theta = F*L^2 / (2*E*I), and fixed-wall bending stress sigma = F*L*c / I.
Read the guide →Geotechnical Excavation Support, USACE Cantilever Steel Sheet-Pile Wall MechanicsCantilever Sheet-Pile Zero-Pressure Depth & Moment Formula
Calculate Rankine Active Ka & Passive Kp Earth Coefficients, Zero-Net-Pressure Depth z0 Below Dredge Line (m), and Active Wedge Overturning Moment at z0 (kN·m/m).
Read the guide →MathCap & Floor Collar: Clamp Numbers Between Min & Max Bounds (MIN & MAX)
Clamp a numeric value to an ordered lower and upper bound using MIN/MAX or MEDIAN, with the same validation for both methods.
Read the guide →Math & TrigCap percentages between 0% and 100% (clamping with MEDIAN)
Clamp attainment and completion ratios cleanly between a lower floor and upper cap in one readable formula with MEDIAN(0, 1, Ratio).
Read the guide →FinancialCap Rate, Net Operating Income (NOI) & Gross Rent Multiplier (GRM)
Calculate simplified annual rental NOI, cap rate, gross rent multiplier, expense ratio and a direct-capitalization scenario from consistent assumptions.
Read the guide →Vacuum & Torch Brazing Metallurgy, AWS C3.4 Capillary Joint Overlap & Wicking RiseCapillary Brazing Joint Overlap & Wicking Rise Formula
Calculate AWS Required Braze Overlap Length (mm), Overlap-to-Thickness Ratio (L/t), Molten Filler Capillary Suction Pressure (kPa), and Vertical Wicking Height (mm).
Read the guide →Engineering & ScienceCapillary Number (Ca) & Bond / Eötvös Number (Bo) Interfacial Scaling
Calculate the viscous-to-interfacial Capillary Number Ca = (mu * U) / sigma and buoyancy-to-capillary Bond (Eötvös) Number Bo = (delta_rho * g * L^2) / sigma for microfluidics, droplets, and enhanced oil recovery.
Read the guide →TextCapitalize only the first letter of a cell (sentence case)
Capitalize the first character and lowercase the rest of a short text label; preserve empty inputs with a blank guard.
Read the guide →Agricultural Phenology & Crop ModelingCapped Growing Degree Days (GDD) Maturity Formula
Calculate USDA / NOAA Modified Capped Growing Degree Days MAX(0, (MIN(T_max, T_upper) + MAX(T_min, T_base))/2 - T_base), Uncapped Bias, Remaining Thermal Units, and Days to Harvest.
Read the guide →Healthcare & ClinicalCaprini Score for Perioperative Venous Thromboembolism (VTE) Surgical Risk
Calculate the weighted Joseph Caprini VTE Risk Score (1*Count_1pt + 2*Count_2pt + 3*Count_3pt + 5*Count_5pt + Age_Points) and stratify surgical DVT/PE prophylaxis from Very Low (0) to High (>= 5).
Read the guide →Mechanical Design & Power TransmissionCapstan and Flat-Belt Friction Formula (Euler-Eytelwein Equation)
Calculate exponential capstan holding-force multiplication EXP(mu * theta_rad) and maximum slip-free flat-belt transmitted power P_kW = (T_1 - T_2) * v / 1000.
Read the guide →Civil, Structural & Geotechnical EngineeringCaquot-Kerisel Log-Spiral Passive Earth Pressure (K_p) Formula vs Planar Coulomb Error
Calculate safe horizontal passive earth pressure coefficient K_p,h under wall-soil interface friction delta using Albert Caquot & Jean Kerisel’s (1948) / Eurocode 7 curved logarithmic-spiral slip surface, avoiding Coulomb’s dangerous overprediction.
Read the guide →Operations, Logistics & EngineeringCarberry Number (Ca) Formula: Observable External Film Mass-Transfer Check in Catalysis
Diagnose external boundary-layer film diffusion falsification in packed-bed catalytic reactors using James J. Carberry’s observable number Ca = R_obs / (k_g * a_p * C_b) and Mears’s < 5% criterion n * Ca < 0.05.
Read the guide →EngineeringCarnot Efficiency & Stefan-Boltzmann Thermal Radiation formulas (Kelvin)
Calculate a two-reservoir Carnot bound and gray-surface radiation to large isothermal surroundings using absolute temperatures.
Read the guide →Engineering & ScienceCarothers Equation: Step-Growth Polymerization Degree (Xn, Xw) & Stoichiometric Ratio (r)
Calculate number-average degree of polymerization Xn = (1 + r) / (1 + r - 2*r*p), weight-average Xw = (1 + p) / (1 - p), and Flory polydispersity PDI = 1 + p in nylon and polyester synthesis.
Read the guide →Geotechnical Dewatering & Slope Stabilization, Casagrande Electro-Osmosis in Soft ClaysCasagrande Electro-Osmotic Clay Dewatering & Power Formula
Calculate Electric Voltage Gradient ie = V/L (V/m), Electro-Osmotic Cathode Water Flow Qe (L/h), DC Rectifier Ohmic Power (kW), and Specific Dewatering Energy (kWh/m³).
Read the guide →Engineering & Fluid MechanicsCasagrande Plasticity Chart (USCS) Formula: Atterberg Plasticity Index & A-Line Soil Symbol
Classify fine-grained soils into USCS Clay vs. Silt (CL, CH, ML, MH) using Arthur Casagrande’s Plasticity Index PI = LL - PL, A-line PI_A = 0.73 * (LL - 20), and LL = 50% compressibility boundary.
Read the guide →Lookup & ReferenceCascading Lookup Across 2 Lookup Tables (XLOOKUP if_not_found & IFNA)
Search a Primary Domestic Catalog first and automatically fall back to a Secondary International/Archive Catalog when missing using XLOOKUP's 4th [if_not_found] argument.
Read the guide →Text FunctionsCase-Sensitive Cell Count & Substring Count (EXACT & FIND)
Count exact uppercase/lowercase matches and case-sensitive substrings where COUNTIF ignores letter case, using row-level --EXACT(A2, $E$2) and --ISNUMBER(FIND($E$3, A2)) helper columns.
Read the guide →Lookup & ReferenceCase-sensitive FILTER, SUM & COUNT using an EXACT helper flag
Use per-row EXACT flags to distinguish case variants, count matching records and sum their numeric amounts.
Read the guide →Lookup & ReferenceCase-sensitive lookup with EXACT, XLOOKUP and INDEX/MATCH
Use a per-row EXACT helper to distinguish letter case in text identifiers, with explicit blank and missing-match handling.
Read the guide →MathCase-sensitive sum and count with EXACT helper flags
Prevent SUMIF and COUNTIF from merging case-distinct IDs like "001XyzAB" and "001Xyzab" by pairing EXACT with SUMPRODUCT.
Read the guide →Math & TrigCash denomination calculator: break amounts into $100, $50, $20, $10, $5, $1 bills
Compute the minimum number of banknotes for cash envelopes and register drawers using INT and sequential MOD remainders.
Read the guide →FinancialCash-on-Cash Return & Equity Multiple (EMx) formulas in Real Estate
Compute a simplified annual pre-tax cash-on-cash ratio and a realized full-cycle distributions-to-equity multiple, without confusing either with annualized return.
Read the guide →Engineering & ScienceCasimir Effect Quantum Vacuum Pressure (1/d^4) & MEMS Plate Force Formula
Calculate the attractive quantum-electrodynamic Casimir pressure P_C = (PI()^2 * hbar * c) / (240 * d^4) in Pascals and stiction force F_C in microNewtons between parallel uncharged conducting plates separated by d nanometers.
Read the guide →Confectionery Rheology & Food Physics, IOCCC / ICA Casson Chocolate Flow ModelCasson Chocolate Yield Stress & Plastic Viscosity Formula
Calculate IOCCC Casson High-Shear Stress tau (Pa), Apparent Pumping Viscosity (Pa·s), Low-Shear 2 s⁻¹ Gravity-Drain Stress (Pa), and Low-Shear Coating Viscosity (Pa·s).
Read the guide →Insurance-Linked Securities (ILS) & Reinsurance Capital MarketsCatastrophe Bond Spread Multiple & Layer Payout Formula
Calculate ILS Catastrophe Bond Risk-Spread-to-Expected-Loss Multiple, Actuarial Net Excess Spread (bps), Proportional Layer Principal Write-Down Principal * MIN(1, MAX(0, (Loss - Attach)/(Exhaust - Attach))), and Surviving Investor Principal.
Read the guide →Healthcare & ClinicalCATCH Rule (Canadian Assessment of Tomography for Childhood Head Injury)
Evaluate Martin Osmond’s 7-item pediatric CATCH head CT rule (0–16 years, GCS 13–15) across 4 High-Risk neurosurgical intervention criteria and 3 Medium-Risk brain-injury-on-CT criteria.
Read the guide →TextCategorize bank or expense descriptions by keyword rules
Map noisy merchant strings like "Card #44 UBER *TRIP" into clean accounting categories using IFS, ISNUMBER, and SEARCH.
Read the guide →Engineering & ScienceCauchy Dispersion Equation: Phase Refractive Index n(λ) & Group Index ng(λ)
Calculate visible/near-IR optical phase refractive index n(λ) = A + B/λ^2 + C/λ^4 and ultrafast pulse group index n_g(λ) = n - λ*(dn/dλ) = A + 3B/λ^2 + 5C/λ^4 across wavelength λ (μm).
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