This paper discusses estimation of US inflation volatility using time-varying parameter models, in particular whether it should be modelled as a stationary or random walk stochastic process. Specifying inflation volatility as an unbounded process, as implied by the random walk, conflicts with priors beliefs, yet a stationary process cannot capture the low-frequency behaviour commonly observed in estimates of volatility. We therefore propose an alternative model with a change-point process in the volatility that allows for switches between stationary models to capture changes in the level and dynamics over the past 40 years. To accommodate the stationarity restriction, we develop a new representation that is equivalent to our model but is computationally more efficient. All models produce effectively identical estimates of volatility, but the change-point model provides more information on the level and persistence of volatility and the probabilities of changes. For example, we find a few well-defined switches in the volatility process and, interestingly, these switches line up well with economic slowdowns or changes of the Federal Reserve Chair. Moreover, a decomposition of inflation shocks into permanent and transitory components shows that a spike in volatility in the late 2000s was entirely on the transitory side and characterized by a rise above its long-run mean level during a period of higher persistence.

The statistic shows the inflation rate in the Netherlands from 1987 to 2023, with projections up until 2029. The inflation rate is calculated using the price increase of a defined product basket. This product basket contains products and services, on which the average consumer spends money throughout the year. They include expenses for groceries, clothes, rent, power, telecommunications, recreational activities and raw materials (e.g. gas, oil), as well as federal fees and taxes. In 2023, the average inflation rate in the Netherlands was about 4.12 percent compared to the previous year.

Economy of the Netherlands

The Netherlands has an open economy, which implies that the country is highly dependent on foreign activities, such as imports and exports. The country’s economic policies and regulations have allowed for the country to highly benefit from strong international relations, however have increased the chances of economic struggles that correspond with the economic situations in other countries as well. The Netherlands is one of the main countries for foreign direct investments in Europe due to its strategic location, superior technological infrastructure as well as international business environment, a reputation that has all but grown more formidable over the years. Additionally, the country’s tourism industry makes up a rather large part of its GDP.

Despite feeling the effects of the global financial crisis of 2008 as well as the Eurozone crisis, many aspects of the Dutch economy are highly prosperous, most notably with its low inflation rates. Unemployment within the country, in spite of a slight increase over the past several years, has remained relatively low in comparison many other European countries that were equally as affected by recession.

This table contains 11 series, with data from 1949 (not all combinations necessarily have data for all years). Data are presented for the current month and previous four months. Users can select other time periods that are of interest to them.

South Africa’s inflation has been quite stable for the past years, levelling off between 3.2 and 6.9 percent, and is in fact expected to stabilize at around 4.5 percent in the future. South Africa is a mixed economy, generating most of its GDP through the services sector, especially tourism. However, the country struggles with unemployment and poverty.

Inflation who?

The inflation rate of a country is an important key factor to determine the country’s economic strength. It is calculated using the price increase of a defined product basket, containing goods and services on which the average consumer spends money throughout the year. They include, for example, expenses for groceries, clothes, rent, utilities, but also recreational activities, and raw materials (e.g. gas, oil), as well as federal fees and taxes. Some of these goods are more volatile than others – food prices, for example, are considered less reliable. The European Central Bank aims to keep inflation at around two percent in the long run.

What happened in 2016?

In 2016, South Africa’s inflation rate peaked at over 6.3 percent, and gross domestic product, and thus economic growth , took a hit, a sure indicator that something was affecting the country’s economic scaffolding: Low growth due to weak demand and an uncertain political future caused a crisis; then-President Jacob Zuma’s alleged mismanagement and unstable reign steeped in controversy and criminal charges even caused the economy’s outlook to be downgraded by ratings agencies. Zuma was relieved of his office in 2018 – ever since, inflation, GDP, and economic growth seem to have stabilized.

In February 2025, the Consumer Price Index including owner occupiers' housing costs (CPIH) inflation rate of the United Kingdom was 3.7 percent, unchanged from the previous month. The inflation rate fell noticeably after the COVID-19 pandemic, but rose sharply between Spring 2021 and Autumn 2022. After peaking at 9.6 percent in October 2022, CPIH inflation declined throughout 2023 and into 2024, falling to 2.6 percent by September of that year, before increasing again in recent months. Cost of living problems persist into 2025 Although it is likely that the worst of the recent inflation surge may have passed, the issues caused by it look set to linger into 2025 and beyond. While the share of households experiencing living cost rises has fallen from 91 percent in August 2022, to 45 percent in July 2024, this share rose towards the end of the year, with more than half of households reporting rising costs in December. Even with lower inflation, overall consumer prices have already increased by around 20 percent in the last three years, rising to almost 30 percent for food prices, which lower income households typically spend more of their income on. The significant increase in people relying on food banks across the UK, is evidence of the magnitude of this problem, with approximately 3.12 million people using food banks in 2023/24. Other measure of inflation While the CPIH inflation rate displayed here is the preferred index of the UK's Office of National Statistics, the Consumer Price Index (CPI) is often more prominently featured in the media in general. An older index, the Retail Price Index (RPI) is also still used by the government to calculate certain taxes, and rail fare rises. Other metrics include the core inflation rate, which measures prices increases without the volatility of food and energy costs, while price increases in goods and services can also be tracked separately. The inflation rate of individual sectors can also be measured, and as of December 2024, prices were rising fastest in the communications sector, at 6.1 percent, with costs falling in the transport and furniture sectors.

The computer consultant industry has pushed forward despite recent economic challenges. Computer consultants have benefitted from the fact that they provide services to clients in all sectors of the economy, meaning demand is more resilient and limiting revenue volatility. The level of business sentiment, which is affected by wider economic conditions, plays a big part in businesses' willingness to spend on computer consultants' services as companies expand by elevating their digital footprint. Industry revenue is expected to climb at a compound annual rate of 3.4% over the five years through 2024 to reach €53.1 billion. However, it should be noted that revenue is somewhat distorted by the large number of computer consultancy companies locating their head or European offices in Ireland. Favourable economic conditions in Ireland had supported business sentiment prior to COVID-19, with Ireland's GDP growth outpacing the rest of the EU. Despite revenue growth slowing in 2020 amid COVID-19, computer consultants were less affected than the wider economy, as companies transitioned to hybrid and remote working, calling on computer consultants to aid the transition. Soaring inflation and geopolitical tensions have subdued business sentiment and expenditure, hindering revenue in 2022 and 2023. Inflation has cooled in 2024, restoring business confidence and starting to ramp up FDI, particularly from the US, which EY reported makes up 60% of projects in Ireland. Revenue is set to jump 4.4% in 2024. Despite demand, intensifying competition from more companies entering the market, huge companies moving in-house and management consultancies have weighed on the average industry profit. Industry revenue is forecast to expand at a compound annual rate of 4.7% over the five years through 2029 to reach €67.0 billion. Continued IT adoption across the economy and technological advancements, like artificial intelligence, cloud computing and 5G mobile technology, will fuel sales for computer consultants. However, a forced hike in the corporate tax level to at least 15% and greater competition will present headwinds for computer consultants in the coming years as it puts pressure on foreign investors to look elsewhere.