Greater investment in our Partners was key to this. We invested significantly in leadership development, for over 250 of our most senior leaders, and will extend that to many more this year. We expanded our apprenticeship programme, with over 900 apprentices enrolling in the year in areas such as retail, LGV driving, vehicle maintenance, hospitality, human resources, project management and finance. We made some of these ‘open entry’ to enable Partners to apply from any part of our business. Among the apprentices that have completed their programmes in the year, 65% passed with distinction where that was an achievable grade. We have taken significant steps in our aim to be the UK’s Healthiest Employer with a review of our Partner dining rooms, including the food and drink we serve, and launching a Wellbeing Champions Network with more than 430 Partners now recruited in more than 130 locations across the country. Partners have accessed our market-leading mental and physical health support services to either prevent health issues or promote quicker recovery, saving more than 60,000 working days across the year. As we have sought to create jobs with more opportunities for Partners to contribute more value through greater use of skills, expertise and judgement, we have increased pay for non-management Partners, with the average hourly rate of base pay rising to £9.16, which is 17%, above the National Living Wage. We expect that average hourly rate of pay to increase by around 4.5% following our April 2019 pay review.
To deliver the level of distinctive difference and innovation we need for the future requires annual investment of £400m-£500m. We anticipated five years ago that market conditions would worsen and took a series of connected steps to strengthen our financial reserves to enable continued investment at this level despite lower profits. These included changes to our pension benefit in 2014, deprioritising investment in new physical space from 2015, and halving the rate of bonus distribution in 2016. We have made a number of divestments of shops and assets in the year and yesterday we also informed Partners that five further Waitrose & Partners shops will be sold to other retailers. We have also made significant organisational changes including moving to single Partnership support functions in many areas. Partner numbers have reduced from 93,800 in January 2015 to 83,900 in January 2019. We will take a series of further steps this year in the move to an even more productive ‘one Partnership’ approach.
In response to the current economic uncertainty, we have built up a strong liquidity position at nearly £1.5bn which is almost double the level five years ago, despite having made deficit reduction contributions of more than £250m to our pension fund over the last three years, which was nearly 97% funded on an actuarial funding basis at January 2019. We have reduced total net debts by over £400m in the year and will pay, from cash, a further £275m to redeem a bond that matures in April 2019.
The decision to pay a Bonus at 3% reflects our continued commitment to sharing a proportion of profits with Partners, while ensuring we continue to strengthen our financial position through times of significant market uncertainty.