The cash-flow analysis page takes the gilts in a portfolio, projects every remaining coupon and redemption, and groups the totals by UK tax year so the income and the capital that fall in each year can be read together.
What the page totals
The cash-flow analysis page starts from the trades booked in a portfolio and projects every coupon and every redemption those gilts have left. It does not show one line per gilt; it totals the dated amounts across the whole portfolio, then lets you change how they are grouped. The result is a schedule of what the portfolio pays, and when, rather than a single valuation figure.
Two controls decide the shape. The group-by control sets the period each column covers, and the flow control sets which kinds of payment the columns carry. Read together they answer the question the page exists for: how much this portfolio's income and capital land in each period, and where the heavy years sit.
The grouping basis
The group-by control offers three periods, and each puts a dated payment into the period that contains its payment date, not the date the gilt was bought.
| Group by | One column is | Where a 5 April payment lands |
| Tax year | A UK tax year, 6 April to 5 April | The tax year that is ending |
| Calendar year | A 1 January to 31 December year | The calendar year that contains 5 April |
| Month | A single month | The month of April |
The tax-year grouping follows the boundary HMRC sets: the UK tax year runs from 6 April to 5 April, so a coupon paid on 5 April belongs to the year that is ending and one paid on 6 April begins the next. The page carries the payment dates from each gilt's own schedule, so a coupon whose date is already fixed drops into its year without any input from you; only a projected index-linked amount is an estimate within that year.
Income and capital are kept apart
The flow control shows the schedule three ways, and the split matters for what the total means. Income is the coupon paid on each holding. Capital is the £100 returned when a gilt matures — inflation-uplifted for an index-linked gilt at its latest published index ratio. Total is the two added together for the period.
- Income columns carry coupons, which are savings income in the tax year of the payment date.
- Capital columns carry redemptions, which are the return of principal and, for a gilt, not a taxable gain.
- Total columns carry both, which is the cash the portfolio receives but not a taxable figure on its own.
- The net coupon income figure in the summary strip applies the portfolio's effective tax rate to the coupon total; the principal is never netted, because a gilt's redemption is exempt from capital gains tax.
The discounting columns
The portfolio page totals the nominal cash you would receive. Each gilt's own cash-flow page is where the same dated flows are also discounted to a present value, and it is worth knowing those columns by name. The NPV column discounts each flow at the gilt's gross redemption yield — the real yield for an index-linked gilt — so the flows sum to the gilt's dirty price. The NPV (par curve) column discounts each flow at the report's fitted par curve at its own term instead, in the same twice-a-year convention, which makes it an estimate from the curve rather than a contractual amount.
The inflation control does a related job. The report projects an index-linked gilt's flows at its latest published index ratio with RPI held flat, so the nominal figures already assume inflation stops rising. The control is the assumed inflation rate — the annual rate a forward projection would grow future RPI at — and the page's inflation-adjusted view discounts the nominal figures back to report-date money at that same rate. Changing it does not re-grow the flows, because the report carries no per-date index-ratio history to grow; it changes the money the flows are expressed in.
Why a year can look larger than expected
A column that spikes is usually a redemption landing in that year, not a change in coupon. A gilt that matures in one tax year puts its whole £100 principal into the capital columns of that year and nothing into the years after, so the total jumps and then falls back. Reading the income columns on their own smooths that out; reading the capital columns on their own shows the redemption years plainly. Neither is the whole picture, which is why the flow control lets you move between them.
A projected index-linked coupon is the other source of a figure that can look surprising, because it is an estimate rather than a contractual amount. It depends on an index value that has not been published yet, so the page marks it as such rather than presenting it as fixed.
What this page is and is not
This page describes how the cash-flow analysis builds its schedule from the trades you have booked, and how to read the grouping and the discounting columns; it is a calculation aid, not investment or tax advice for any reader's circumstances. Every figure is only as good as the trades it is built from, so a missing trade or a wrong settlement date carries into the schedule. The primary source for a tax-year boundary is HMRC; the primary source for a gilt's own payment dates and coupons is the gilt's record and the day's report. Keep the trades current in your portfolio and the projection follows.