BIS PCI Revision Policies
Revised: 21-Jul-2011
BIS Output Price Indices for Direct Labour
The quarterly BIS Output Price Indices for Direct Labour are first published as provisional indices and will be published as firm indices one quarter later.
The indices are not normally held provisional for more than one quarter, but this may happen if the series used to construct these series are held provisional longer than normal.A provisional index may change. Changes between the first provisional index and a firm index are almost always less than 1%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed in exceptional circumstances: to correct publication errors or in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS Output Price Indices for New Constructionand Repair and Maintenance
The quarterly BIS Output Price Indices are first published as provisional indices. Updated provisional indices will be published one quarter later based on additional information received. Firm indices will be published six months after the first provisional indices were published. The firm indices will incorporate additional data received but are not expected to change significantly. Changes between the first provisional index and a firm index are almost always less than 2%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed to correct publication errors or in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS ALLCON All Construction TPI
The quarterly BIS All Construction Tender Price Indices are first published as provisional indices. Updated provisional indices will be published in subsequent quarters until all the input indices have been firmed up (typically four or five quarters after the first provisional indiceswere published). The likelihood and extent of changes to indices will reduce quarter by quarter. Firm indices will be published once all the input indices have been firmed.Changes between the first provisional index and a firm index may be in the order of 3%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed to correct publication errors or in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS PUBSEC Tender Price Index of PublicSectorBuilding Non-Housing
The quarterly BIS Tender Price Index of Public Sector Building Non-Housing is first published as a forecast seven quarters ahead of the publication quarter. The forecast is reviewed prior to each publication date and changes will reflect both changes in latest calculated indices and revised outlook.
A provisional index will first be published for the quarter prior to the publication quarter. The first provisional index will be based on a small sample and the index is likely to change over the next two quarters as additional project indices become available, but the index continues to be held provisional. Changes between the first provisional index and a firm index are typically around 1%.
The index is normally heldprovisional for three quarters, after which it is published as a firm index. The index value may change as the index becomes firm, but changes will normally be small as the sample is unlikely to have increased and any change is likely to come from the subsequent quarter as a result of the smoothing process.
Once published as firm, the index will not be changed for revisions in the input data. A firm index will only be changed in exceptional circumstances: to correct publication errors or in the event of a change in methodology. If a revision is necessary then the index will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS PUBSEC Tender Price Index of PublicSectorBuilding Non-Housing: Functional Study and Location Study
The quarterly location and functional studies for BIS Tender Price Index of Public Sector Building Non-Housing are first published as provisional for the quarter prior to the publication quarter.
The index is normally held provisional for three quarters, after which it is published as a firm index. The provisional index may change at each publication and may change as the index becomes firm. Changes between the first provisional index and a firm index are typically below 2%.
Once published as firm, the index will not be changed for revisions in the input data. A firm index will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the index will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
BIS ROADCON Tender Price Index of Road Construction
The quarterly BIS Tender Price Index of Road Construction is first published as a provisional index for the quarter prior to the publication quarter. The first provisional index will be based on a small sample and the index is likely to change over the next two quarters as additional data become available, but the index continues to be held provisional.
The index is normally held provisional for three quarters, after which it is published as a firm index. The index value may change as the index becomes firm. Changes between the first provisional index and a firm index may be in the order of 5%.
Once published as firm, the index will not be changed for revisions in the input data. A firm index will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the index will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS ROADCON Tender Price Index of Road Construction: Value, Road Type and Location Studies
The quarterly value, road type and location studies for BIS Tender Price Index of Road Construction are first published as provisional for the quarter prior to the publication quarter.
The index is normally held provisional for three quarters, after which it is published as a firm index. The provisional index may change at each publication and may change as the index becomes firm. Changes between the first provisional index and a firm index may be in the order of 8%.
Once published as firm, the index will not be changed for revisions in the input data. Firm indices will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the index will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
BIS TPISH Tender Price Indices of Social Housebuilding
The quarterly BIS Tender Price Indices of Social Housebuilding are first published as provisional indices for the quarter prior to the publication quarter. The first provisional indices will be based on a small sample and the indices is likely to change over the next two quarters as additional data become available but the indices continue to be held provisional.
The indicesare normally held provisional for three quarters, after which they are published as firm indices. A provisional index may change. Changes between the first provisional index and a firm index are typically less than 2%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
Annual indices will always be updated to reflect changes in the quarterly series.
BIS TPISH Tender Price Index of Social Housebuilding: Location Study
The quarterly location study for BIS Tender Price Indicesof Social Housebuilding is first published as provisional for the quarter prior to the publication quarter.
The indices are normally held provisional for three quarters, after which they are published as firm indices. A provisional index may change at each publication, including as the index become firm. Changes between the first provisional index and a firm index are typically less than 1%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.
BIS Resource Cost Indices
The quarterly BIS Resource Codes Indices are first published as provisional indices for the quarter prior to the publication quarter.
The indicesare normally held provisional for only one quarter, after which they will be published as firm indices. Indices may be held provisional for longer if the indices used to construct them are held provisional longer than normal. The provisional indices may change as they become firm. Changes between the first provisional index and a firm index are almost always less than 2%.
Once published as firm, the indices will not be changed for revisions in the input data. Firm indices will only be changed in exceptional circumstances: to correct publication errorsor in the event of a change in methodology. If a revision is necessary then the indices will be marked as ‘Revised’ thereafter. Changes in methodology will be recorded under notes and definitions.Any major changes or revisions will be pre-announced, where practicable, together with the reasons for revisions and how they are handled.