Getting Started
1. Where do I find the Custom Metric Builder?
Click + Metric in the portfolio table. The Custom Metric Builder appears at the top of the quick-add metric selector.
2. How do I set up a formula?
Each metric you add under Metric Inputs is assigned a label (A, B, C, etc.). Use those labels in the formula bar with standard operators:
+ addition
– subtraction
* multiplication
/ division
^ exponent
Parentheses are supported. Example: A * B multiplies metric A by metric B per position.
Common Formula Questions
3. How do I divide each position's value by the sum of the entire column?
Use SUMCOLUMN() to reference the column total. For a metric A:
A / SUMCOLUMN(A)
This divides each row by the column total. For a more complex expression, for example a product of two metrics:
(A * B) / SUMCOLUMN(A * B)
4. How do I show % of gross within a group-by?
Use the built-in % of Book Gross: it shows each position's share of total portfolio gross exposure.
Note: SUMCOLUMN() scopes to the group in a group-by view, so each group sums to 100%. To get each position as a share of the total portfolio (not just within-group), use the % Book Gross built-in directly rather than a custom formula.
5. Can I multiply two metrics together?
Yes. Add both metrics as inputs (A and B) and write the formula:
A * B
This works for any combination of built-in, imported, or user-defined metrics.
6. How do I handle blank or missing values in a formula?
To default to a fallback value when a metric is blank, use ABS(A)>0 to check if a value is present. For example, to default to 1 when A is blank:
IF(ABS(A)>0, A, 1)
7. How do I calculate the square root of a metric?
Use the exponent operator with 0.5:
A ^ 0.5
Example: to get the square root of % Idio Variance, add it as A and use A ^ 0.5.
8. What does % Weight mean in the Custom Metric Builder?
% Weight is calculated as Net Invested $ / Gross $ (or / AUM $, depending on the portfolio mode). It reflects each position's weight as a proportion of the portfolio.
9. Why is my custom formula returning blanks for some tickers?
If an input metric has no data for certain tickers, the formula will return blank for those rows. This commonly happens with metrics that require sufficient data coverage. For example, Implied Volatility requires options coverage to calculate.
If you encounter this, consider using a metric with broader coverage. For volatility, Annual Total Vol (%) or a returns-based standard deviation transform are good alternatives.
10. How do I calculate a % change over a custom number of trading days?
Use the Formula Builder, not the Custom Metric Builder. Add a Price column to your table, right-click the column header, select Formula Builder, choose % Change, and set the lookback to your desired number of trading days.
Note: the current day's data point uses the live price rather than the previous close.
11. Why can't I use an existing custom metric or transformed column as an input?
Using another custom metric or a Formula Builder transform (e.g. a Beta column) as an input inside the Custom Metric Builder is not currently supported. This is on the roadmap.
Workaround: re-enter the underlying base metrics directly as separate inputs (A, B, C) in the new formula, rather than referencing the existing column.
12. Can I use the Custom Metric Builder on a Dashboard table?
Not currently. The Custom Metric Builder is only supported in the portfolio table. The option does not appear when adding metrics to a Dashboard table. This is a known limitation and has been flagged to the team.
13. Can I view custom formula columns in the charts?
Yes. Custom metrics created in the Custom Metric Builder are available in the Visualize panel under the Custom Formulas category. You can select them on the X axis, Y axis, or Size.
14. Can I add a custom formula column to the Side by Side view?
Not currently. Custom formula columns are not supported in Side by Side. The Delta column that appears automatically in that view is a built-in feature for standard metrics.
15. Does a custom metric work in a group-by view?
It depends on how the metric is configured. Some aggregation settings may not behave as expected in a group-by view. If you run into this, reach out to support with your metric configuration and they can help diagnose it.
16. Can I use a market or index return as an input (e.g. for Jensen's Alpha)?
Not currently. The Custom Metric Builder works at the asset level using per-position metrics. Standalone index returns or portfolio-level returns cannot be added as inputs. Jensen's Alpha is not yet supported as a built-in metric.
Sharing Custom Metrics
17. Are custom metrics shared with my team or are they individual?
By default, custom metrics are individual. To share them across your team, reach out to [email protected] to be added to a shared team. Once on the same team, any new custom metrics created will be visible to all team members.
A few things to note:
Metrics created before team sharing was enabled will not automatically appear for others. They need to be recreated.
Team members may need to refresh or restart the app to see newly shared metrics.
Team members can all contribute, and edit access can be controlled per metric.
18. My colleague can't see the custom metrics I shared: why?
This usually happens for one of two reasons:
The metric was created before your accounts were added to the same team.
The app needs a refresh. Have your colleague close and reopen Arcana.
If the metrics were created before team sharing was set up, recreate them and they will be visible to the team going forward.
19. How do I calculate a realized beta column to a custom benchmark?
This uses the Formula Builder, not the Custom Metric Builder. Add a Total Return or Residual Return column, right-click the column header, select Formula Builder, choose Beta as the transform, set the target index (e.g. SPX), configure the lookback window, and save.
For any questions, reach out to [email protected]