First, I’ll analyze the company’s profile based on the data.  

The balance sheet shows stable but capital-intensive operations (over €9.6 billion in property, plant, and equipment). Equity grew significantly from €3.69 billion to €4.89 billion, but it relies heavily on non-current borrowings and government grants. The cash flow statement shows strong operating cash flows (€1.57 billion), but investing activities consumed €1.64 billion, indicating big infrastructure spending.  

From the market data, swap rates moved sharply upward in 2022, increasing the cost of fixed-rate debt. The iBoxx EUR Non-Financial IG subordinated spread widened in 2022 compared to 2021, meaning hybrid bond financing became more expensive.  

Hybrid bonds are useful for companies wanting to preserve credit ratings while raising capital, as rating agencies usually assign partial equity credit. The company already has a large amount of borrowings and grants, so it can probably access senior debt and bank financing without over-relying on hybrids. Given the rise in subordinated spreads and the company’s regulatory/utility-like profile (stable revenue), too much hybrid reliance is unnecessary and more costly than senior debt.  

A small to moderate hybrid allocation could be justified for rating management and capital structure flexibility, but 50–100% would be excessive and expensive. A 25% allocation maintains some equity credit benefits without drastically increasing financing costs.  

<answer>25%</answer>