Rydym yn defnyddio mynegeion prisiau, megis y Mynegai Prisiau Defnyddwyr (CPI) i asesu chwyddiant - mesuriad o'r gyfradd cynnydd mewn prisiau ar gyfer nwyddau a gwasanaethau. Un modd o ddeall y CPI yw meddwl am fasged siopa fawr sy'n cynnwys detholiad o'r nwyddau a'r gwasanaethau a brynir gan aelwydydd. Mae'r CPI yn amcangyfrif newidiadau i gyfanswm cost y fasged hon.
The Consumer Prices Index including owner occupiers’ housing costs (CPIH, not a National Statistic) 12-month inflation rate was 2.6% in April 2017, up from 2.3% in March.
The rate has been steadily increasing following a period of relatively low inflation in 2015 and is at its highest since June 2013.
Air fares were the main contributors to the increase in the rate in April 2017, although this balanced out a downward effect of similar magnitude in March 2017 and is due to Easter falling later than last year.
The Services Producer Price Inflation (SPPI), formerly the Corporate Services Price Index (CSPI), are constructed from a statutory quarterly survey. The SPPIs are primarily a suite of individual price indices that provide information on price change for a limited range of service industries. Each SPPI captures quarterly changes in the price received for services provided by UK businesses to other UK businesses and government. These individual price indices are also aggregated together to create a "service industry" SPPI with limited coverage (it does not provide full coverage of the "service sector").