Factor and Sector Exposure Look Through Calculator

Purpose and model boundary

This calculator looks through up to 12 funds at once. For each fund you enter a name, its weight (its share of your portfolio), its exposure to five common factors and its weight in each of the 11 sectors. The calculator adds them up, each fund weighted by its share, to show which way your whole portfolio leans on value, size, momentum, quality and low volatility, how much of it sits in each sector, which fund puts it there, and which sectors are at or above the share you set as your limit. The main result is the weight of the largest sector; beside it are the largest sector, how many sectors are at or above the limit, their names, and the part of the portfolio outside the 11 sectors. Three tables and two charts show the same results in full.

Every figure on this page is computed by the spreadsheet; the page adds nothing to it. To see the expected return and the risk of the same holdings, use the Portfolio Expected Return and Volatility Calculator; to bring a portfolio back to its target weights, use the Asset Allocation Rebalancing Calculator.

The model is educational. It does not look inside any fund, it holds no factor or sector data of its own, and it is not financial, investment, tax or legal advice.

Inputs and units

• Your funds, a table of up to 12 rows. An empty row anywhere is skipped; a row with any value in it is a listed fund and needs all seven values. At least 1 fund is needed.
  • Fund: a name, used to label the tables.
  • Weight: the fund's share of your portfolio, from 0% to 100%.
  • Value, Size (small companies), Momentum, Quality and Low volatility: the fund's exposure to each factor, from -2 to 2. 0 is the market's own exposure; a positive number leans toward the factor and a negative one away from it. Take every exposure from one source, on one scale, because different sources score factors on different scales.
• Each fund's weight in the 11 sectors, a second table whose rows carry the same numbers as the funds. Each weight is from 0% to 100%. Give every fund you list all 11, typing 0% where it holds none; a blank is never read as 0. What a fund holds outside the 11 sectors, such as cash or bonds, is not classified, so a row may add up to less than 100% but never more. A row for a fund you have not listed is not read.
• Concentration limit for one sector, from 1% to 100%. A sector at or above it is flagged. 15% is shipped; it is a common rule of thumb, not a regulation.

Weights and the limit are percentages; factor exposures are plain numbers.

Governing relationships

Write Kᵢ for the weight you entered for fund i and Wᵢ = Kᵢ ÷ Σ K for its weight used, so the weights used always add up to 100%. Write xᵢₖ for fund i's exposure to factor k and sᵢⱼ for its weight in sector j. Then:

• the portfolio's exposure to factor k is Σᵢ Wᵢ xᵢₖ;
• its weight in sector j is Σᵢ Wᵢ sᵢⱼ;
• fund i's part of sector j is Wᵢ sᵢⱼ, so each sector's weight is the sum of its funds' parts;
• the part not classified is 100% minus the 11 sector weights;
• sector j is flagged when its weight is at or above the concentration limit, so a sector exactly at the limit is flagged.

A factor exposure within 0.000000000001 of 0 reads as no tilt. The largest sector is the one with the largest weight, the first in the list on a tie, and reads None at 0% when no fund holds any of the 11 sectors.

Calculation sequence

The spreadsheet first checks every input and counts the listed funds. It divides each weight by their total and, for each listed fund, checks that its sector row is complete and adds up to no more than 100%. It then works out the five factor exposures, the 11 sector weights, each fund's part of each sector, the part not classified, the flags, their count and names, and the largest sector. A block of consistency checks confirms the arithmetic before the status is returned.

Outputs and interpretation

The headline is the weight of the largest sector. Beside it are the largest sector, the number of sectors at or above the limit, their names (None when there are none) and the part of the portfolio not in any of the 11 sectors. The first table gives each factor's exposure with its direction, Toward, Away or None. The second gives each sector's weight beside the limit, with Yes for a sector at or above it; its last row is the part not classified, which is never flagged. The third gives each fund's part of each sector, so its largest numbers show which funds drive a concentration. The fund weights as entered, added up, and the workbook's self-check are returned to the API and MCP.

Flags are results, not a status: a portfolio with a sector at or above the limit still reads OK. Most stock portfolios have at least one sector above 15%.

With the shipped example, one illustrative broad stock fund at 100% and a limit of 15%, the portfolio is the fund: information technology is the largest sector at 30.0% and the only one at or above the limit, and 0.5% is not classified. Its tilts are as typed: away from value (-0.05), size (-0.10) and low volatility (-0.05), toward momentum (0.02) and quality (0.10).

With that fund at 60% and a bond fund at 40% that holds no stocks and has no tilts, every tilt and sector weight is 60% of the stock fund's: information technology is 18.0%, still the one sector at or above 15%, quality is 0.06 and size -0.06. The part not classified is 0.6 × 0.5% + 0.4 × 100% = 40.3%.

With a US stock fund at 50%, an international stock fund at 30% and a small-company fund at 20%, information technology is 21.2% and financials 16.2%, so two sectors are flagged, and the small-company fund tilts the whole portfolio toward size (0.095).

The first chart draws the five factor exposures as bars from 0, to the right toward a factor and in red to the left away from it. The second draws the 11 sector weights as columns with the limit as a dashed line; a column at or above the line is red.

Validation and status logic

The workbook evaluates the conditions below from top to bottom and returns the first matching status.

NOT VALID is a refusal, not a numeric answer: every number reads zero, every name is blank and the tables are empty. CHECK accompanies a computed result but calls for the stated review. The self-check is reported separately as arithmetic-integrity evidence; it does not replace this ordered status chain.

Assumptions and limitations

Every factor exposure and sector weight is an input you take from each fund's own reports; the model holds no data and does not check them. It is a weighted average, right for any one consistent scale, but exposures from different sources may not be comparable. It does not look through to single stocks or countries, does not measure overlap between the holdings of different funds, does not regress returns on factors, and does not follow how exposures and sector weights change over time. Fees and taxes are not modelled. The sector names are the 11 sectors of the Global Industry Classification Standard, used as labels only; the funds in the examples are illustrative, not real funds.

Restrictions and non-computing states

This calculator enforces its numeric limits, the 1 to 12 listed funds, a complete sector row for every listed fund and sector rows of no more than 100% before it accepts a result. A blank factor or sector cell of a listed fund is refused rather than read as 0.

Errors and warnings

A request rejected by the page's input limits is not a computed result. A transport or service failure cannot establish a fresh workbook answer. Review the workbook's References and Disclaimer, and check any plan with a qualified professional before using a result for a real decision.

Sources and further reading

Every fund weight, factor exposure and sector weight comes from the inputs, not market data. The workbook's References sheet lists the same four sources. They describe the names and methods the model uses; they do not endorse this calculator.

• MSCI, "The Global Industry Classification Standard (GICS)": the names of the 11 sectors used as the column labels. GICS was developed by MSCI and S&P Dow Jones Indices, which hold its trademarks. Only the names are used: no classification of any security is reproduced, and you enter each fund's sector weights yourself (retrieved 2026-10-19).
• E. F. Fama and K. R. French, "Common risk factors in the returns on stocks and bonds", Journal of Financial Economics 33(1), 1993, pages 3 to 56: the size and value factors (retrieved 2026-10-19).
• M. M. Carhart, "On Persistence in Mutual Fund Performance", The Journal of Finance 52(1), 1997, pages 57 to 82: the momentum factor, which the article adds to the size and value factors as one-year momentum in stock returns (retrieved 2026-10-19).
• Microsoft Support, "SUMPRODUCT function": the workbook function that multiplies each fund's weight by its exposure and adds the products (retrieved 2026-10-19).

The MSCI and Microsoft pages were read in full for this page. Carhart's article was opened and its abstract and description of the size, value and momentum factors were read; the rest of its text was not. For Fama and French, the citation details (authors, title, journal, volume, pages, year and identifier) were confirmed from the bibliographic record only; the full text was not read for this page. Each entry above describes only what the calculator takes from it.

This is an educational estimate, not financial, investment, tax or legal advice. Factor exposures and sector weights change over time, and different data providers measure factors on different scales; use one source for all your funds, and check any plan with a qualified professional.