> ## Documentation Index > Fetch the complete documentation index at: https://docs.tilt.now/llms.txt > Use this file to discover all available pages before exploring further. # Explain and test an account's rebalance > Break down why an account sits away from its benchmark, and compare today's rebalance with a change before you make it. An account's **Overview** can run today's rebalance as a simulation. Use it to see why the account sits away from its benchmark, and what a change would do to its trades, tax and tracking error before you save anything. Every run starts from the account's saved settings and the latest prices. Nothing is saved or traded. Two sections sit below **Performance**: | Section | Use it to | | - | - | | **Why this account differs from its benchmark** | Break today's rebalance down by cause, and compare it with one of the account's own decisions changed. | | **Try a change** | Compare today's rebalance with changes you enter: tickers, a cap on every position, gains or losses to realize, a different calculation, or a series of rebalances. | To open them, click **Clients**, open the client, and select the account by name. A [prospect's](https://docs.tilt.now/advisor/model-a-prospect.md) accounts don't show these sections. Each row has a button that starts its run. While the run works, the button reads **Comparing…**. A run can take a few minutes. The result opens below the row. Close it with the close button in its corner, or click the row's button again, such as **Compare again**, to run it with what's entered now. ## 1. Break down the account against its benchmark In **Why this account differs from its benchmark**, click **Break down** on **What moves it away from its benchmark**. ![Why this account differs from its benchmark section with the note Each row runs today's rebalance. The first breaks it down by cause. The rest compare it as saved with one of the account's decisions changed. Rows: What moves it away from its benchmark with a Break down button, Without tax-aware trading with a Compare button, and Rebalanced fully onto its model with a Compare button.](https://mintcdn.com/tilt/lA5ehs_vS8XyA19e/images/advisor/what-if-differs-section.jpg?fit=max\&auto=format\&n=lA5ehs_vS8XyA19e\&q=85\&s=d101202f4c0531c9d463b58f38fc9d1a) An account with no saved tilts and an assigned model. The breakdown shows today's rebalance as saved: | Part | What it shows | | - | - | | Figures | **Tracking error** against the benchmark, **Tickers held**, the **Largest position**, and **Cash**. | | **Where it sits off benchmark** | How far the account sits from its benchmark, split by cause. Each holding's distance counts under its main cause. Each cause shows an **Amount** in dollars, its points **Of the account**, and its **Share** of the whole distance. | | **Furthest from the benchmark** | The holdings furthest from their benchmark weight, with the **Benchmark** and **Account** weight, the **Difference**, and the **Main cause**. A ticker the benchmark holds and the account doesn't can appear here. | | **Factor exposure** | The account's style factors against the benchmark. Smaller style factors, and countries, currencies, industries and the market, fold into links that open them. | | **Held by restrictions** | The tickers the account's restrictions hold in place, and how: **Not bought**, **Not held**, **Not traded**, or **Held at benchmark weight**. | The causes are: | Cause | What it covers | | - | - | | **Saved tilts and views** | The account's tilts and the views behind them. | | **Tax-loss harvesting** | The rebalance's tax decisions: gains it avoids realizing and losses it harvests. | | **Staying put to save trading costs** | Holdings the rebalance leaves in place because moving them would cost more than it gains. | | **Restrictions and rules** | The account's restrictions and the model's rules. | | **Fund expenses** | Funds held or skipped for their expense ratios. | | **Yield** | The income the rebalance aims for. | | **Unexplained** | Distance no cause above accounts for. | ## 2. Change one of the account's decisions The rest of **Why this account differs from its benchmark** compares today's rebalance as saved with one decision changed. Click **Compare** on a row: | Row | Compares today's rebalance with | | - | - | | **Without** a saved tilt, such as **Without Low Carbon +5%** | The same rebalance without that tilt. The section lists a row for each tilt saved on the account's sleeves. | | **Without tax-aware trading** | The same rebalance with tax ignored. | | **Rebalanced fully onto its model** | A rebalance onto the model, the way a [transition](https://docs.tilt.now/advisor/transition-analysis.md) runs it. An account without a model doesn't have this row. | The comparison puts the account **As saved** beside the account with the change, and shows the **Difference**: | Figure | Meaning | | - | - | | **Tracking error** | Tracking error against the benchmark after the rebalance. | | **Estimated tax** | The tax on the gains the rebalance realizes. | | **Traded** | The value of everything the rebalance buys and sells. | | **Gains realized** | The net gains the rebalance realizes. | | **Tickers held** | How many tickers the account holds afterwards. | | **Largest position** | The largest holding's weight afterwards. | | **Cash** | The account's cash weight afterwards. | **Trades the change adds** lists each ticker whose trade differs, with the trade and the ticker's weight both ways. A difference too small to show reads **No change**. A figure Tilt doesn't know, such as tax on an account without tax lots, reads **—**, and so does its difference. ## 3. Try your own change **Try a change** compares today's rebalance as saved with a change you enter. Each row runs on its own: | Row | Enter | | - | - | | **Change tickers** | A ticker and what to do with it: **Exclude**, **Hold at** a weight, **Tilt toward by** or **Tilt away by** a percent, or **Never sell**. Click **Add a ticker** to change several at once. | | **Cap every position** | The largest weight any position may have. Tickers with their own bounds keep them. | | **Realize** | An amount of **Gains** or **Losses** to realize this year. The rebalance sells lots to land near the amount. | | **Calculate differently** | **Tax ignored**, **Trading costs counted**, or **Wash sales matched by share, first in first out**, which needs the account's tax lots. | | **All together** | Every change entered above, in one run. It can also turn off one saved tilt, and it needs at least two changes. | The ticker search offers the tickers today's rebalance can change: the account's holdings and its benchmark's. When a change names a ticker outside them, the row names the ticker. ![Try a change section with rows for Change tickers set to Exclude VWO, Cap every position at 40%, Realize with an amount and a Gains or Losses choice, Calculate differently set to Saved settings, All together listing the entered changes, and Over time with Monthly, 12 rebalances and Harvest losses deeper than 5% chosen. Each row has a Compare button.](https://mintcdn.com/tilt/lA5ehs_vS8XyA19e/images/advisor/what-if-try-a-change.jpg?fit=max\&auto=format\&n=lA5ehs_vS8XyA19e\&q=85\&s=33c71c5704abd3d98e56df8df548b86f) Excluding VWO and capping every position at 40%, ready to compare. ## 4. Compare rebalances over time **Over time** runs a series of rebalances on dates a month or a quarter apart, ending today. Each rebalance starts where the one before ended. The series runs once as saved and once along each path you choose. 1. Choose **Monthly** or **Quarterly**, and how many rebalances. 2. Open **Paths to compare** and choose up to seven paths. A path follows a different calculation, such as **Harvest losses deeper than 5%**, **Harvest every loss**, **Rebalance onto the model** or **Trading costs counted**, or another of your firm's saved models. 3. Click **Compare**. Every path starts from one shared rebalance on the date before the first. When your choices add up to more rebalances than one series can run, the row says so. The result lists each path's **Estimated tax**, **Gains realized** and **Traded** across the series, and its **Tracking error at the end**, beside the account as saved. The totals include the shared rebalance. **Estimated tax at each rebalance** shows every date on every path. A total reads **—** when any of its rebalances has an unknown figure. ## When a run doesn't finish The row says why. Two reasons need something outside the row: | Message | What to do | | - | - | | **A ticker the account holds has no recent price, so today's rebalance can't be run.** | Check the holding on the **Holdings** tab. The run works again once the holding has a price. | | **No rebalance meets all of the account's rules at once.** | The change conflicts with the account's rules. Loosen the change, or review the rules on the **Setup** tab. | ## Ask Tilt Agent Tilt Agent runs the same simulations and answers with the same results. Open **Chat** with the account open, so Tilt Agent [knows which account you mean](https://docs.tilt.now/tilt-agent/ask-about-page.md), or name the account in your question. For example: > Why does this account differ from its benchmark? > What would excluding VWO do to this account's tax and tracking error? > What would rebalancing this account fully onto its model trade? > Compare three monthly rebalances of this account as saved and harvesting every loss. To keep a change, save it on the account's **Setup** tab. [Tailor an account](https://docs.tilt.now/advisor/tailor-account.md) covers the settings there. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.