Detailed below is the key financial data relating to XYZ Company Ltd (XYZ or the Company) for the respective years. XYZ's principal activities involves the development, manufacturing, and sale of technological products for the consumer market. Ratio 2019 2020 2021 Return on Equity 10.8% -3.1% -1.4% Return on Assets 3.0% -0.8% -0.3% Cost of Sales to Sales 75.6% 78.5% 74.8% Research and Development Expenses to Sales 6.3% 6.9% 6.6% EBITDA to Sales* 10.2% 2.3% 5.6% Liabilities to Assets 72.4% 75.3% 76.9% 75 days 61 days 38 days Days Inventory * EBITDA is earnings before interest, tax, depreciation, and amortisation. (a) Analyse the trend in XYZ's profitability with supporting reasons, based on the information provided.