A BBC analysis published on 26 October says economic growth in each quarter this year has been about twice as fast as the OBR forecast in March. It says independent forecasters had also predicted slower growth.
According to the BBC, this is the fastest growth in the first eight months of a year since 2017, leaving aside the reopening after lockdown.
The analysis also points to pressures on the public finances. It says borrowing has been higher than forecast. It also says CPI inflation rose more than expected to 3.5% in September, which in its view makes a Bank Rate rise likely.
The BBC says revised statistics may give the OBR cause to rethink last year's downgrade to long-term growth, and that the Iran war settling could improve the outlook. It adds that there are reasons for the Chancellor, John Healey, to postpone the toughest decisions, such as funding for defence and social care.
The BBC also notes there have been "almost no Budget leaks" ahead of Wednesday's statement on 28 October.
These are the BBC's assessments rather than government or OBR figures, and they have not been independently checked.