Table A. Year-on-Year Inflation Rates, All Items
In Percent
(2018=100)

Overall Inflation

Zamboanga del Norte's inflation rate for all-income households declined to -1.0 percent in April 2025, down from 0.2 percent in March 2025. In comparison, the inflation rate in March 2024 was much higher, recorded at 4.9 percent. Additionally, the inflation rate for all-income households across the entire Zamboanga Peninsula decreased to 0.0 percent in April 2025, down from 0.6 percent in March 2025. In comparison, the inflation rate in March 2024 was much higher, recorded at 4.7 percent (Figure 1 and Table A).

Attributes in the Downtrend of the Overall Inflation

The decrease in overall inflation in April 2025 was mainly driven by the higher annual changes in the following commodities;

1. Food and Non-Alcoholic Beverages at -3.1 percent from -0.6 percent of the previous month; and
2. Transport at -3.6 percent from -1.8 percent of the previous month.

In addition, the following commodity groups registered lower inflation rates during the month of April 2025 were:

1. Furnishings, Household Equipment and Routine Household Maintenance, 1.5 percent from 2.1 percent;
2. Clothing and Footwear, 2.6 percent from 2.8 percent;
3. Food and Non-Alcoholic Beverages, -3.1 percent from -0.6 percent; and
4. Transport, -3.6 percent from -1.8 percent.

In contrast, the following commodity groups registered a higher inflation rate during the month were:

1. Recreation, Sport and Culture, 6.1 percent from 5.7 percent;
2. Housing, Water, Electricity, Gas and Other Fuels, 0.3 percent from 0.1;
3. Personal Care, Miscellaneous Goods and Services, 2.0 percent from 1.7 percent;
4. Health, 5.3 percent from 4.3 percent;
5. Alcoholic Beverages and Tobacco, 5.7 percent from 5.5 percent; and
6. Restaurants and Accommodation Services, 5.6 percent from 4.7 percent.

Meanwhile, the inflation rate that remained unchanged from the previous month were the following commodity groups:

1. Information and Communication, at 0.1 percent;
2. Education Services, at 3.9 percent; and
3. Financial Services, at 0.0 percent.

Main Contributors to the Headline Inflation

The top three commodity groups contributing to the April 2025 overall inflation were the following:

1. Food and Non-Alcoholic Beverages with -3.1 percent inflation at 147.2 percent share to the overall inflation; and
2. Transport with -3.6 percent inflation at 29.8 percent share to the overall inflation.

Table B. Year-on-Year Inflation Rates in Zamboanga del Norte, All Items January 2020 to April 2025 in Percent
(2018=100)

Top 5 Contributors in Zamboanga del Norte April 2025 Inflation:

1. Rice with -15.8 percent inflation from -8.0 percent in the previous month;
2. Corn with -20.3 percent inflation from -22.7 percent in the previous month;
3. Gasoline, café and the like with -12.2 percent inflation from -5.4 percent in the previous month;
4. Other pelagic fish with -5.0 percent inflation from -2.5 percent in the previous month; and
5. Onions and shallots, with -12.3 percent inflation from -1.6 percent in the previous month.

The inflation rate for Food at the provincial level in April 2025 was reported at -1.0 percent, declining from 0.2 percent of the previous month (Table C). Meanwhile, food inflation for the month of April 2024 was reported at 4.1 percent.

Table C. Year-on-Year Inflation Rates in Zamboanga del Norte,
All Items April 2024 to April 2025 by Commodity Group

In Percent (2018=100)

Graph 1. Inflation Rates for the bottom 30% income households in
Zamboanga del Norte, January 2025 to April 2025 by Commodity Group

Bottom 30% Income Household

Zamboanga del Norte's inflation rate for the bottom 30% income households declined to -2.4 percent in April 2025, down from -1.0 percent in March 2025. In comparison, the inflation rate in April 2024 was much higher, recorded at 7.9 percent. The bottom 30% of income households' inflation rates from January to April 2025 showed a downward trend, averaging -0.1 percent (Figure 4 and Graph 1).

Main Sources of Deceleration

The top three main sources of deceleration to the April 2025 bottom 30% were the following:

1. Food and Non-Alcoholic Beverages with -4.8 percent inflation at 90.7 percent share to down trend inflation; and
2. Transport with -4.5 percent inflation at 9.3 percent share to down trend inflation.

Top 5 Contributors in Zamboanga del Norte, April 2025 Inflation for the Bottom 30%:

1. Rice with -16.0 percent inflation from -8.0 percent in the previous month;
2. Corn with -20.3 percent inflation from -22.7 percent in the previous month;
3. Gasoline, café and the like with -12.2 percent inflation from -5.4 percent in the previous month;
4. Other pelagic fish with -5.0 percent inflation from -2.5 percent in the previous month; and
5. Onions and shallots, with -12.3 percent inflation from -1.6 percent in the previous month.

Purchasing Power of Peso

In Zamboanga del Norte, the purchasing power of the peso was recorded at Php0.81, which explains that you needed Php123.8 for a basket of food and non-food commodities in April 2025, which only cost Php100.00 in the year 2018.

Technical Notes:

Consumer Price Index (CPI)

The CPI is an indicator of the change in the average prices of goods and services commonly purchased by consumers.

Uses of CPI

The CPI is most widely used in the calculation of the inflation rate and the purchasing power of peso. It is a major statistical series used for economic analysis and as a monitoring indicator of government economic policy.

Computation of CPI

The computation of the CPI involves consideration of the following important points:

a) Base Period

• The base year is a reference period, usually a year, at which the index number is set to 100. It is the reference point of the index number series. The CPI is rebased from the base year 2012 to the base year 2018.

b) Market Basket

• Market basket refers to a sample of goods and services commonly purchased by households.

c) Weighting System

• The weighting pattern uses the expenditures on various consumer items purchased by households as a proportion of total expenditure.

d) Formula

• The 2018-based CPI series uses the same method of computation as the 2012-based CPI series, which is Chained Laspeyres formula.

e) Geographic Coverage

• CPI values are computed at the national, regional, and provincial levels, and Highly Urbanized Cities.

Inflation Rate (IR)

The rate of change of the CPI expressed in percent, Inflation is interpreted in terms of the declining purchasing power of peso.

It is computed using the following formula;

Headline Inflation

Refers to the rate of change in the CPI, a measure of the average standard basket of goods and services consumed by a typical family.

Purchasing Power of Peso (PPP)

Shows how much the peso in the base period is worth in the current period. It is computed by
getting the reciprocal of the CPI and multiplying the result by 100 as follows:

How does the PSA compile the CPI for the bottom 30% income households?

The CPI for the bottom 30 % income households is compiled by the PSA to measure the changes of prices of commodities commonly purchased by families that belong to the bottom 30% income decile. The process of price collection and CPI computation is the same as that of the CPI for all income households. However, there is a separate market basket and weights for the CPI for the bottom 30% income households.

ANDRES S. TAPALES, JR.
(Statistical Specialist II)
Officer-In-Charge