Canada International Merchandise Trade volume and price index: dyes, pigments and petrochemicals
20 March 2025 - Written by ML
This report summarizes Canada’s international merchandise trade performance in dyes, pigments, and petrochemicals (NAPCS category 263) from 2017 to 2024, based on Statistics Canada data (Table 12-10-0168-01). It combines insights from export and import chart analyses, focusing on price and volume indices, terms of trade (ToT), and, growth rates. The analysis highlights key trends, volatility, and external influences shaping this sector.
We begin with an overview of trade indices over time, depicted in the line chart below. Each index is plotted on its own facet to show its trajectory since 2017.
Figure 1: Historical trade in dyes, pigments and petrochemicals (Monthly, Not Seasonally Adjusted)
To quantify the patterns discussed, we compile summary statistics for the growth rates of each series. We look at the mean and standard deviation (SD) of each relevant growth rate over the full period. The table below presents these statistics for export price MoM, export volume MoM, import price YoY, and import volume YoY.
| Statistic | Export.Price..MoM. | Export.Volume..MoM. | Export.Price..YoY. | Export.Volume..YoY. | Import.Price..MoM. | Import.Volume..MoM. | Import.Price..YoY. | Import.Volume..YoY. |
|---|---|---|---|---|---|---|---|---|
| Mean | 0.38 | 0.97 | 5.16 | -0.30 | 0.69 | 0.52 | 7.77 | -0.15 |
| SD | 3.38 | 14.62 | 17.35 | 14.84 | 5.74 | 12.57 | 13.31 | 16.03 |
We next examine the growth rates of these indices to assess volatility and momentum, using both month-over-month (MoM) changes and year-over-year (YoY) changes for exports and imports. This perspective highlights short-term fluctuations and longer-term annual shifts in trade.
Figure 2: Price and volume month on month growth rates in exports and imports
Figure 3: Price and volume year on year growth rates in exports and imports
Another way to visualize the volatility is a heatmap of growth rates over time. Below, we map each period’s growth rate as a color, which helps quickly identify periods of extreme change: red for contractions and blue for expansions.
Figure 4: Heatmap of month on month growth rates in imports and exports
Figure 5: Heatmap of year on year growth rates in imports and exports
The heatmap visually confirms the earlier observations. The export price MoM row (bottom) is mostly a light color (near white), indicating many months of minimal change, with only a few pale red or blue patches corresponding to moderate drops or rises.
A broadly consistent pattern to exports is shown for short term change in imports.
In contrast, the export and import volume YoY charts alternate between deeper reds and blues, reflecting the severe contractions in 2020 (dark red segment) and strong expansions in 2021 (dark blue segment), followed by continued variability into 2023–2024
To investigate seasonality, the time series is decomposed using the STL (Seasonal-Trend Decomposition using Loess1) method by Cleveland et al. (Cleveland et al., 1990). This method separates each index into trend, seasonal, and residual components for analysis.
Figure 6: STL Decomposition of unseasonally adjusted Trade Data - Export Price
Figure 7: STL - Export volume
Figure 8: STL - Import price
Figure 9: STL - Import volume
The variation in the amplitude of seasonal effects between different indices, such as stronger seasonal patterns in volume indices compared to price indices, which might reflect different underlying economic factors.
Both IMP PRICE IDX and IMP VOL IDX show consistent repeating patterns, with the seasonal component indicating periodic fluctuations likely tied to calendar cycles. Both EXP PRICE IDX and EXP VOL IDX also exhibit clear seasonal patterns, with the volume index showing a stronger amplitude, suggesting more pronounced seasonal effects in export volumes compared to prices.
To organize the key observations, the following table summarizes the range of values for each component across the datasets:
| Dataset | Data.Range | Remainder.Range | Seasonal.Range | Trend.Range |
|---|---|---|---|---|
| IMP PRICE IDX | 110-180 | -10 to 20 | -5 to 10 | 110-160 |
| IMP VOL IDX | 70-130 | -20 to 20 | -5 to 10 | 80-100 |
| EXP PRICE IDX | 90-140 | -5 to 10 | -2 to 2 | 100-130 |
| EXP VOL IDX | 90-130 | -20 to 20 | -10 to 10 | 90-110 |
we assess the terms of trade (ToT) for this segment, defined as the ratio of the export price index to the import price index (expressed as a percentage). An increasing ToT implies that export prices are rising faster than import prices, which can indicate improving trade competitiveness or earning power for Canada (each unit of export buys more imports). A declining ToT suggests the opposite.
Figure 10: Terms of Trade as ratio of export prices to import price
Canada’s trade in dyes, pigments, and petrochemicals from 2017 to 2024 is marked by strong price growth—exports up 40% and imports peaking 80% above 2017—but stagnant volumes for both. Export prices grew consistently, while import prices surged and then cooled, impacting the ToT, which saw a sharp decline in 2022-2023 before recovering in 2024. Volumes remained volatile, with no net growth, reflecting supply or demand constraints. Demand appears inelastic, and import-export volume links are weak, suggesting independent market dynamics. External shocks like COVID and inflation drove major changes, with 2024 showing stabilization but no long-term ToT advantage. Stakeholders should focus on hedging price risks, addressing volume constraints, and monitoring global trends to navigate ongoing uncertainty.
This report examines monthly international merchandise import and export price and volume indexes for dyes, pigments and petrochemical in Canada. Source for the indices is from Statistics Canada (Table 12-10-0168-01). The four specific Vector IDs are: 1566913117; 1566912967; 1566914935; 1566914785 that relate to import volume, import price, export volume and export price. These vectors represent the dyes, pigments and petrochemical industry which is 263 on the North American Product Classification System (NAPCS). The data series use customs data and are unadjusted for seasonality. The indices are Laspeyres weighted.
The data was extracted via a methodology detailed here, spans multiple years and is analyzed through various visualizations and tables generated in R. Our goal is to identify historical patterns, assess seasonality, and explore recent trends, providing insights into the industry’s workforce dynamics.
[The STL (Seasonal-Trend Decomposition using LOESS) method is a robust and versatile approach to decomposing a time series into three distinct components: trend, seasonal, and remainder (or residual). It was developed by Robert B. Cleveland and colleagues in 1990 and is useful for time series with strong seasonal patterns that may vary over time.]↩︎