Distribution of Neptunian planets across the orbital period space, where three regimes are differentiated: a significant deficit of planets at periods ⪅3.2 days (i.e the Neptunian desert), a moderately populated region at periods ⪆5.7 days (i.e. the Neptunian savanna), and an overdensity of planets between these regimes (i.e. the Neptunian ridge). The histogram error bars were computed as the square root of the quadratic sum of the weights.